WILDWOOD, N.J. — President Trump told his supporters at a raucous rally on Tuesday evening that Representative Jeff Van Drew of New Jersey, who recently left the Democratic Party, was a symbol of the future. Without evidence, he said that an increasing number of Americans were “disgusted” by congressional Democrats who, he said, are “obsessed with demented hoaxes, this crazy witch hunt and deranged partisan crusades.”
“They’ve spent the last three years and probably even before I came down on that beautiful escalator with our beautiful future first lady,” Mr. Trump said, “trying to overthrow the last election, and we will make sure that they face another crushing defeat in the next election.”
The president traveled to Wildwood, a boardwalk town on the southern end of the Jersey Shore that is deserted in the winter, to return a political favor for Mr. Van Drew, a former moderate Democrat who last month switched parties and pledged his “undying support” for Mr. Trump. Mr. Van Drew had also been a strong anti-impeachment voice in the House before he made the switch, saying the Republican Party was a “better fit.”
Mr. Van Drew said he had requested a rally when Mr. Trump asked how he could help.
“They’re trying to steal that election,” Mr. Trump said, “and Jeff had the guts to defy the left-wing fanatics in his own party and to stand tall in defense of our Constitution, our freedom and democracy itself.”
At the rally, Mr. Van Drew was immediately embraced by Trump supporters as one of their own. Mr. Trump lost New Jersey by 14 points to Hillary Clinton, his Democratic challenger in 2016, but the rally drew thousands who hope to change the political fortunes for local Republicans, starting with Mr. Van Drew’s re-election.
“He has the conservative values that we want,” James Toto, a councilman in Somers Point, N.J., said as he joined the line outside. “He has conservative values more so than some Republicans do. He wants to make sure people can be independent and on their own.”
Tim Murtaugh, the Trump campaign’s communications director, said that campaign officials were betting that Mr. Van Drew represented the type of politician that moderate Democrats might want to hear more from.
“We think a lot of Democrats across the country are looking for a new home,” Mr. Murtaugh said at the rally.
Senator Cory Booker of New Jersey, a former 2020 presidential candidate, said the opposite in a fund-raising email sent to supporters of his Senate re-election campaign.
“Trump will be spreading his platform of hatred and bigotry to help re-elect Jeff Van Drew, the congressman who shamefully switched his party affiliation from Democrat to Republican during the impeachment process,” the email said.
The rally location — essentially empty in January — gave attendees an opportunity to bundle up and engage in a spiritual takeover of the area for a few days. Beachside motels opened up to board an influx of supporters.
On Monday evening, the Trump faithful overran local bars, singing renditions of “Sweet Caroline” late into the night. Hundreds of people were lined up outside the Wildwoods Convention Center, staking out their claim to the front of the line with plastic chairs. Near the boardwalk, Trump-themed recreational vehicles were parked in the shadow of dormant roller coasters.
“There is nobody in the middle of winter,” the president remarked, “and those streets are packed all the way back to the airplane, probably.”
Mr. Trump, who on his way out of Washington did not stop to answer questions as his impeachment defense team wrapped up its case in the Senate, used his time at the rally podium to fight back — and to train the spotlight back on his own re-election campaign. He promised that his campaign would be signing up “millions and millions” of registered independent and Democratic voters, and bragged about his poll numbers.
“I had the best polls that I’ve ever had since being elected,” he said, “the best we’ve ever had. Remember, I used to go over polls, but I only used to talk about them when I was doing well otherwise.”
The president’s approval rating has hovered at around 43 percent, but an increasing number of Americans are voicing support for hearing witnesses in his impeachment trial.
Mr. Trump is facing several roadblocks in his administration’s quest for a speedy acquittal in the Senate. His former national security adviser, John R. Bolton, wrote in a book draft that Mr. Trump had held up aid to Ukraine to further his political ambitions, making it harder for Senate Republicans to abstain from requesting that witnesses offer further testimony.
On Tuesday evening, cracks in the united front that the White House has tried so hard to build with Senate Republicans started showing when Senator Mitch McConnell of Kentucky, the majority leader, told a closed-door meeting of Republicans that he did not currently have the votes to block Democrats from calling witnesses at the trial.
While he targeted the topic of impeachment at times, calling out individual Democrats like Speaker Nancy Pelosi by name, Mr. Trump’s hourlong address largely hewed to the same red-meat themes he has introduced to his base.
“I never even knew the swamp was this bad,” Mr. Trump, who frequently attends high-dollar donor events, told the rapt crowd. “A lot of bad people in the swamp. Bad people in the swamp.”
Mr. Trump introduced several inaccurate claims, including falsely accusing the Obama administration of choosing not to end the AIDS epidemic — even though President Barack Obama directed billions to accelerate efforts to find a cure.
He also claimed that the Republican Party would protect patients with pre-existing medical conditions. “We are protecting people with pre-existing conditions and we always will,” said Mr. Trump, whose administration has taken steps to weaken such protections.