DES MOINES — Four Democratic presidential candidates hoping for breakout performances in the Iowa caucuses next week spent Thursday in Washington listening to testimony in the Senate impeachment trial of President Trump.
But the president himself headed to Des Moines for a rally to fire up his supporters before the caucuses on Monday. It was his second rally in three nights this week; he spoke Tuesday in Wildwood, N.J.
Unlike the Democrats, Mr. Trump does not face a competitive contest in Iowa, where his two Republican challengers — Joe Walsh, a former Illinois congressman, and Bill Weld, the former governor of Massachusetts — have failed to make any dent in Mr. Trump’s support.
But the Trump campaign views a show of force before the caucuses as an opportunity to try to slow any momentum the winning Democrat hopes to gain from the close race. And Monday will be the first chance voters have to show their support for Mr. Trump since the 2016 election.
Trump officials said the caucus would be an important milestone for a campaign that never really ended since Mr. Trump began with his famous escalator ride in Trump Tower in 2015. “This will be the first time his supporters are able to take part in the process that begins his re-election,” said Tim Murtaugh, a Trump campaign spokesman.
Before the rally on Thursday night at Drake University, Mr. Trump made a brief stop in Warren, Mich., where he spoke to manufacturing workers the day after he signed the revised North American Free Trade Agreement into law.
Mr. Trump’s trade deals are a key part of his re-election message. But it was clear that the impeachment trial — which Republican senators are hoping to wrap up quickly without hearing from additional witnesses like John R. Bolton, the former national security adviser — was on his mind.
“I’ve kept my promise, not only my promise of loving the people of Michigan, but my promise of taking care of it so other countries aren’t ripping us off,” Mr. Trump told the crowd gathered at Dana Incorporated, a major auto parts manufacturer of axles, transmissions and other key components in Warren, an industrial city north of Detroit. “You remember the tax cut? It was the biggest tax cut in the history of our country, and what do they do? They impeach you. It’s frankly a disgrace to our country.”
At one point as he spoke, the crowd of Michigan officials, Trump supporters and Dana employees chanted, “Four more years.”
James K. Kamsickas, the chief executive of Dana Incorporated, said his company was “a strong supporter” of the United States-Mexico-Canada Agreement.
“Like our customers, Dana relies heavily on an integrated international supply chain,” he said. “We believe this will allow for North American vehicle production to remain competitive globally.”
The Trump campaign plans to follow up on the Des Moines rally with a blitz of appearances at caucus sites on Monday by roughly 80 cabinet secretaries, administration officials and members of Congress to generate enthusiasm among Iowa Republicans.
Mr. Trump already has deep support in the state. Jeff Kaufmann, the chairman of the Iowa Republican Party, has been a strong Trump supporter who has echoed the president’s description of a Democratic Party defined by “left-wing nuts.” Campaign officials have tried to reward Mr. Kaufmann’s loyalty with presidential visits designed to motivate other state chairmen to follow suit.
The president last held a campaign rally in Iowa in Council Bluffs in October 2018 as part of his push before the midterm elections. In June, he traveled to the state to speak at the Iowa Republican dinner on the same day that Vice President Joseph R. Biden Jr. was crisscrossing the state, giving voters a preview of what a general election matchup between the two would look like.
Since then, however, Mr. Biden has slipped from his front-runner status in the state, where Senator Bernie Sanders of Vermont has emerged on top in a handful of polls. But Mr. Sanders as well Senators Elizabeth Warren of Massachusetts, Amy Klobuchar of Minnesota and Michael Bennet of Colorado spent the day in the Senate chamber.
Steve Friess contributed reporting from Warren, Mich.