At Missouri Rally, Trump Vows to Eliminate ‘Lingering Stench’ at the Justice Department

The president spoke at length about how his candidacy and electoral victory in 2016 had defied predictions, inviting his cheering audience to relive the night of the election with him. He imitated news anchors calling states in his favor, and described his election as “one of the greatest nights in the history of our country, but far less importantly, one of the greatest nights in the history of television.”

The dynamic reflected the strategy Mr. Trump has embraced as he campaigns for Republicans this year, hoping to transfer his own popularity among core party supporters to candidates who need a highly motivated base of voters to succeed. But it carries risks as well; the president’s popularity here has declined since 2016, with a recent NBC News/Marist poll showing his unfavorable rating at 50 percent. And Republicans concede that his unique brand of popularity may not be transmittable to others on the ballot.

“If he was on the ballot, there would be no question we would win both” the House and Senate, Representative Billy Long, Republican of Missouri, told the crowd as he warmed up the arena before Mr. Trump’s appearance. “Without it, we need your support.”

Mr. Trump acknowledged the challenge and the historic trend against the president’s party holding Congress in midterm elections, saying: “I know that the votes are sort of against us, but I don’t know why. We have the greatest economy in history.”

Praising Mr. Hawley as a star, Mr. Trump criticized Ms. McCaskill as a slave to Democratic leaders who had opposed his agenda at every turn, charging that she wanted to give undocumented immigrants health care and education benefits.

“Democrats even want to give welfare and free health care to illegal aliens, all paid for by you, the great American taxpayer,” Mr. Trump said, twisting their position. “Republicans want to protect the safety net for truly needy Americans, not for illegal aliens.”

He was apparently referring to his administration’s proposal, under consideration for months, to punish immigrants for accepting food stamps, public housing and other government benefits to which they are entitled — but with one major mischaracterization: the rule would apply to legal immigrants, not people who are undocumented.