A lawsuit by the Justice Department challenging a potential narrow loss by the GOP Senate incumbent in Alaska reflects a new tactic by the president to try to shape the election results.

© Haiyun Jiang/The New York Times

“There is no legal excuse” for the failure of 18 polling sites to open for early voting, a state lawmaker said.

© Kerry Tasker/Reuters

With moves in Alaska and California, the department has stepped up interventions in the midterm elections as the president’s instrument of unmediated executive power.

© Doug Mills/The New York Times

Election officials across the state received letters from the agency saying if they fail to comply, they “risk significant federal scrutiny.”

© Philip Cheung for The New York Times

No obvious legal authority supports a pre-emptive effort to block the certification of Alaska’s Senate election if the Republican incumbent narrowly loses.

© Kerry Tasker for The New York Times

The department, in a highly unusual lawsuit, argued that confusion over candidates with similar names could taint the election result.

© Doug Mills/The New York Times

The Justice Department has opened an inquiry into Mr. Lewandowski. President Trump has not jumped to his defense.

© Haiyun Jiang for The New York Times

The charges intensified the administration’s efforts to go after the law enforcement and intelligence personnel who cast doubt on unsubstantiated claims that Joseph R. Biden Jr. engaged in corrupt dealings in Ukraine.

© Erin Schaff/The New York Times

Election officials say they worry the administration could use its own unsubstantiated claims to contest the vote in November.

© Doug Mills/The New York Times

The Trump administration is escalating its fight with California ahead of next month's midterm election, warning that local officials who process and tabulate ballots submitted by suspected noncitizen voters are putting themselves at risk of criminal investigation and potential prosecution.