The 2026 midterm cycle is projected to be the most expensive election cycle in US history, with candidates across the board raising money at a record pace. And voters are taking notice: Big-donor groups tied to issues like Israel policy, AI, and crypto have become major flashpoints in primary races in both parties.

Campaign spending alone doesn’t determine elections. The recent Democratic Senate primary in Michigan was the most expensive Democratic congressional primary in terms of outside spending — but ended with Abdul El-Sayed overcoming a major financial disadvantage to win the nomination. In California, billionaire Tom Steyer spent over $200 million of his own money on his bid for governor, but lost. 

But the ever-rising tide of cash helped fuel voter concerns about corruption and the campaign finance landscape is only getting more confusing: In June, the Supreme Court struck down limits on how much political parties can spend in coordination with their own candidates, further blurring the line between what candidates raise directly and what parties can spend on their behalf.

How can voters follow the money? How much difference does outside spending actually make in the outcomes of these races? And how much can candidates rely on grassroots donors to push back? 

Danielle M. Thomsen, a professor of political science at the University of California Irvine and author of the 2025 book, The Money Signal: How Fundraising Matters in American Politics, has spent years studying these questions. The conversation has been lightly edited and condensed for clarity.

Let’s start with a race like the recent Michigan Senate Democratic primary. Abdul El-Sayed was massively outspent by outside interest groups like AIPAC and still won. Does that change how you think about money’s role in politics, or is it generally consistent with what we know?

The bulk of my research is looking at US House primaries, and I think you could probably draw similar conclusions for Senate primaries, except that in most cases, Senate primaries have way more information. So in the case of Michigan, I think people knew largely what the choices were. And after you get to that stage, largely through money and advertising and voter outreach, and campaigning, after that point, money might matter less because voters become more familiar with choices. But this is a really steep hurdle in most congressional primaries.

I think that people forget how low information these contests usually are. Many primary voters really don’t know much about candidates. I think in the Michigan Senate example, that was less true. Money isn’t irrelevant, but when you have other pieces of information, that can override money. And furthermore, in that case, both of the candidates were spending millions of dollars in the primary. I mean, this is just so unique in a lot of ways.

Is there a minimum level of money congressional candidates need to be viable? Do we know?

The average for non-incumbent successful candidates in open seat primaries is about three to $400,000 in the first quarter. And if you look at incumbents who lost or struggled, well, their challengers for the most part, are not, you know, broke jokes. They’re raising $200,000 to $300,000 in their first quarter, which resembles what quote unquote “open seat candidates” are raising too in many districts. Maybe not your super wealthy districts like in New York or in California, but in many districts, $300,000 in your first quarter is a really good showing. So I would say money is money, and early money in particular is a prerequisite.

And that’s not going to mean that if you raise a lot of money, you definitely will win. That’s never been the case and that’s still not the case. But it does matter for you, it matters for who is seen to be seriously in the mix, who is perceived to be relevant. And in this cycle, just like in most cycles, virtually all contenders who are either successful or are seen as successful show support through early fundraising.

Your view is that fundraising works largely as a signal of viability and strength — to the public, party leaders, media, everyone. Is that the consensus view in political science, or are there competing frameworks?

In many ways the argument of my book is not very groundbreaking if you talk to practitioners, but it hasn’t been empirically documented in the ways that I did. Some other people in political science call attention to endorsements. The other theory is that money matters not as a signal of viability but for material goods — so to buy advertisements, office infrastructure, hiring staff, and consultants.

“Among those who run, rich candidates are also more likely to win.”

Within a candidate’s total haul, does it matter where the money comes from, like a broad base of small donors, a candidate self-funding, or a super PAC backed by a few wealthy people?

I’ve recently begun to look at this. With a graduate student of mine, Ryan Mundy, we collected data and wrote a paper on why wealthy candidates are likely to win. Because it’s not just the case that rich candidates are more likely to run, which most people know and prior research has shown, but among those who run, rich candidates are also more likely to win.

And what we show is that rich candidates are more likely to raise early money. In particular, they’re more likely to raise large-dollar donations, which then have a greater return in subsequent quarters.

What do we know about candidates who fully self-fund?

So I’ve learned that fully self-funded candidates, meaning those who don’t supplement with financial support from others, typically lose. Self-funding on its own is not as valuable as getting money from others, and in particular large-dollar donations from others.

However, many, many candidates supplement with their own money. Something like 40 percent of non-incumbent general election winners self-fund at least $10,000. I think people don’t really understand the prevalence of self-funding as a supplement, and how that keeps some people disadvantaged, particularly those who can’t self-fund at all.

For some self-funders, I think some of them just don’t want to raise money. It can be pretty unpleasant! And while self-funding with no supplemental money from others is overwhelmingly a bad strategy, there are a couple handful of people who have done this and won out of our sample that looked at 2014 to 2024. There were 407 non-incumbent general election winners in that period. And 17 of them did bankroll at least 90 percent of their first-quarter dollars and won. So not very many, but there are a handful of exceptions who do it and win, and they are all rich. So funding is complicated.

And on the “friends and family” side of early money, who’s actually writing those first checks?

Almost all early money comes from individual contributors. Most of that is itemized, so contributors over $200. Most of our elections are driven by the upper class. On average non-incumbent general election winners are getting like 50 percent of their early money from max-out donors, meaning people who pay the maximum of $6,600. Who can afford to pay that? Not normal Americans. It’s basically politically engaged, politically connected upper-middle class people who know people who run for office.

And the other thing is most of them are not repeat donors! Most of them don’t even give to more than one candidate. Because they’re probably just giving to the one rich person they know who is running for office that year. That’s why in political circles the first quarter is called the “friends and family quarter” — that’s when political consultants tell candidates to open up their Rolodex and call everybody they know from when they started kindergarten to who their coworkers are now.

Is there a point, empirically, where more spending stops helping or even backfires? I’m thinking of a case like Tom Steyer in California.

So the assumption has always been that money has diminishing returns. That goes back to Gary Jacobson’s work from forever ago. But nobody in political science puts a number on it. What they do is they say things like, Oh, the relationship is positive until at some point it goes down.

When outside groups pour money into a race, like AIPAC now, or the charter school lobby and the NRA in earlier cycles, can that spending become politically useful to the candidate it’s targeting, from backlash or otherwise?

“Most candidates are raising the bulk of their money from itemized donors. And most money is still from large donors.”

Yeah, so I don’t think there’s actually good research on this. I don’t think there’s enough information. But I think in general most people don’t know where money comes from. So the backlash is minimal. I’ve asked candidates who raised a lot of money from self-funding, “Did your self-funding ever come up?” And they’d say, “No, it never came up. I thought it would either help me, to show that I wasn’t beholden to special interests, or it would hurt me because I didn’t have the support that having fundraising money from others would demonstrate. But it didn’t come up.” Another candidate who raised a lot of money out of state told me that while it was raised a few times by people on Twitter, no one in person ever asked him about it.

Many people don’t know their own members of Congress. So you can imagine why there wouldn’t be a backlash, because people don’t know enough for there to be one — except in these cases where it does become an issue, like the recent Michigan Senate Democratic primary. It’s certainly part of the narrative for candidates like Elizabeth Warren, her stance against big money is a big part of her persona, same with Bernie Sanders and AOC. But those are real celebrity candidates.

In the 2010s, small-dollar fundraising was talked about as a democratizing counterweight to big money, but I remember reading that research found it could also make politics more polarized. Where did that political science literature land, and has the rise of small donors changed anything as Super PACs and mega-donors have grown more powerful?

So I would say the research is exactly how you describe it. There are so many studies that have shown that small-dollar donors tend to be more liberal Democrats and more conservative Republicans. So they are coming from the ideological edges of the spectrum. And there’s a lot of evidence of that. So that’s the finding, that’s the literature.

If you look at how candidates raise money by and large today, it’s not coming from small donations or unitemized donations. Most candidates are raising the bulk of their money from itemized donors. And most money is still from large donors.

So your read is that, despite all the attention on small-dollar fundraising, the underlying picture hasn’t shifted much either direction?

There’s a tendency to look at the cases that don’t conform to the rule rather than the rule. Like Eric Cantor [who lost in 2014] and AOC [who won in 2018]. In some cases, the losers raised way more than the partisanship of the district in those cases would predict, and then you have candidates who raised no money and unpredictably won. So there’s always this tendency to prop up the exceptions to the rule. In political science, though, we like to look at the rule.

Tom Tiffany, the new Republican nominee for governor in Wisconsin, is not just a passive supporter of President Donald Trump’s lies about the 2020 presidential election. He is an active promoter of them.

In December 2020, when he was a member of Congress, he signed on to a Texas lawsuit seeking to invalidate Joe Biden’s victory. On January 6, 2021, he voted against certifying the results in Pennsylvania and Texas just hours after rioters threatened to kill his colleagues. He has stated he would have overturned Wisconsin’s results too, and just this year endorsed an FBI investigation into the state’s elections. And though the national climate in 2026 favors Democrats, Wisconsin is a closely divided state: Tiffany could beat the odds and win the general.

There is, in short, a very real chance that someone who doesn’t believe American elections are legitimate may soon be supervising them in one of the 2028 presidential cycle’s most important swing states.

It’s not just Wisconsin. In each of the other most critical 2028 states — Michigan, Georgia, Pennsylvania, Arizona, and Nevada — Republicans have chosen an election denier as their nominee for governor, secretary of state, or both. If any of these candidates win, they will have at least some degree of authority over the administration of elections in a state that could determine the outcome of the next presidential election. 

So could the outcome of the 2026 midterms ultimately lead to a stolen election in 2028, as some are already warning? Election experts say it’s very unlikely.

State election laws contain numerous overlapping checks on interference from top officials. The judiciary has a pretty strong track record in stopping election malfeasance. A reform to the Electoral Count Act, passed quietly during the Biden presidency, significantly improved federal protections against election interference. And in 2028, the man uniquely responsible for previous pushes to invalidate the 2020 election won’t be on the ballot.

“[There are many] reasons why one should not be concerned,” said Rebecca Green, the co-director of the Election Law Program at the College of William and Mary. “Even in circumstances where there is a single partisan in control of a state’s election process, there are numerous checks on that power.”

That said, the risk isn’t zero. There is a remote chance, if the election is extremely close, that a well-placed election denier could swing the outcome. And even if they don’t outright steal an election, someone like Tiffany could still use their office to damage the electoral system in some pretty important ways.

“We have to be walking between complacency and alarmism,” said Rick Hasen, an expert on election law at UCLA. “Both of those are bad.”

Why the 2028 election is more secure than you think

Election law varies from state to state. Most of the time, the state’s secretary of state (SOS) is in charge of elections, but sometimes it’s the state board of elections. Sometimes the SOS is directly elected, and sometimes they’re appointed by the governor. 

But in broad strokes, there are three ways for governors or an allied SOS to attack an election. They can try to suppress opposition voters before the voting starts, by (for example) purging them from the rolls or putting insufficient polling stations in their neighborhoods. They can try to interfere during the vote count, by trying to disqualify outparty ballots or even falsifying the vote count. Or they can try to interfere afterward, by refusing to certify election results.

“Courts have shown themselves to be pretty good against election denialism. That’s true of both Democratic and Republican appointed and elected judges.”

Rick Hasen, UCLA election expert

Each of those is exceptionally, perhaps even prohibitively, difficult to pull off — even for a committed election denier.

Voter suppression is hard because the tactics are legally limited. Current federal law bans voter roll purges within 90 days of the election, which allowed Democrats to simply re-register voters disqualified in previous Republican purges (though the Supreme Court may overturn this provision in an upcoming case). Impediments like polling station placement are, per Hasen, hard to target; they are most likely to affect low-income and low-propensity voters, who have trended Republican in recent elections.

Interfering with the counting of votes is made difficult by what Green terms “adversarial election administration”: basically, the fact that partisans from both parties are involved in multiple different stages of the counting process. Every state has strict rules governing the counting process, and observers from both parties can see if they’re being breached in the other party’s favor. If there is an irregularity, courts are empowered to step in and correct it.

And it is simply illegal for governors or secretaries of state to refuse to certify legitimate elections. State laws in all relevant battleground states allow courts to issue a writ of mandamus requiring officials to certify duly counted results, which they have done repeatedly since 2020 when Republican-controlled county election boards withheld certification.

“Courts have shown themselves to be pretty good against election denialism,” Hasen said. “That’s true of both Democratic and Republican appointed and elected judges.”

The 2022 reform to the Electoral Count Act added several additional safeguards for presidential elections specifically, including a requirement that Congress defer to court determinations on electoral legitimacy if a governor attempts to defy them. 

And all of that assumes that a Republican who denied the result of the 2020 election would necessarily attempt to steal future elections. That may not be the case. 

“Just because you have partisan control of an election, and just because that person has cast doubt on previous elections, doesn’t mean that person is not going to be committed to running a fair election,” Green said.

Such a sentiment may sound naive, but it also may reflect the reality of post-Trump politics. The president was the driving force behind the attempt to overturn the 2020 election; his insistence that he did not lose, and his iron grip on the hearts and minds of the GOP base, pushed the party onto grounds that its other leaders clearly feared to tread. 

While Republicans certainly attempted to stack the electoral deck in their favor prior to Trump, these brazen attempts to overturn or steal legitimate elections are a product of his time in office. Whether he has permanently changed the Republican Party into an entity that will regularly reject elections they lose is very much an open question.

Why electing election deniers could still matter

All of this should give us some comfort about the upcoming state-level races: It is simply very hard for a governor or SOS to steal a presidential election even if they want to. While American democracy is weak in many different ways, the security of its election architecture specifically is actually one of its strong points.

But even the most impregnable-seeming fortresses can be breached. And there are reasons to worry that, in an extreme case, an election denier in key positions could well damage the integrity of the 2028 presidential election.

In a 2022 paper, the law professor Lisa Marshall Manheim argued that conventional legal analysis has proven inadequate for addressing the threat of election subversion. While legal experts are correct to say that the law makes stealing an election hard, the most dangerous threat to US elections — Trump’s 2020 campaign — was essentially extra-legal in character.

While American democracy is weak in many different ways, the security of its election architecture specifically is actually one of its strong points.

While “superficially” operating through the legal system, Trump was actually asking officials from Congress on down to engage in obviously unlawful behavior. When Trump asked Georgia Secretary of State Brad Raffensperger to “find” just enough votes to overturn the state’s results, or for Mike Pence to find the “courage” to nullify the results on January 6, he wasn’t asking these two men to act according to their legal duties. He was asking them to step beyond law, to embrace a reading of their office’s powers so obviously absurd that it amounts to declaring the text of the law to be no limit at all.

This is the nightmare scenario: one in which officials in key positions simply decide that they no longer have to follow a good-faith reading of the law. If enough officials in the right places decide to cast off legal shackles, no carefully crafted statute can stop them. We will, as Hasen put it, exit the domain of law into “something else”: the politics of raw power.

Anyone who endorsed Trump’s lies about the 2020 election — let alone actively attempted to act on them — has already shown a degree of contempt for election law. That means that one can’t rule out a similar display of contempt in the future, only this time with the power to turn that into impactful defiance of law.

It’s vastly too early to say the conditions under which such a radical breach might occur, in 2028 or in the future. A lot depends on the makeup of the Republican Party; whether leaders after Trump embrace or downplay his hostility to the electoral system itself. But we now know that the risk is there. And the more election deniers we have in key positions, the greater the odds are that the risk becomes real — even if the baseline probability remains low in absolute terms.

This connects to another, more insidious risk: that electing election deniers could exacerbate the ongoing crisis of electoral confidence since 2020.

Even if Tiffany or someone like him doesn’t try to outright prevent or nullify Democratic victories in their state, they could still declare that they lack confidence in the result’s integrity. That they tried to run a fair election, but that Democrats or the courts prevented them from doing so — and thus, despite their lack of legal powers to stop it, that they believe the election to have been compromised or even stolen.

This may not lead to a series of January 6s across the country. But even if it didn’t, it would deepen the lack of trust Republican voters have in the electoral system. If Republicans post-Trump continue to believe that Democrats are engaged in widespread cheating, that could contribute to an environment where the kind of extra-legal shenanigans Manheim warned of could look more tempting.

So while it is quite unlikely that the 2026 elections will lead to a crisis in 2028, it could play a role in dashing the possibility that American democracy moves on from the dangerous Trump-era fighting over elections. And as long as that fighting persists, another 2020-style crisis will remain a live possibility.