INDIANOLA, Iowa ― In his first campaign event since ending a week in Washington for the impeachment trial of President Donald Trump, Sen. Bernie Sanders (I-Vt.) made a forceful case on Saturday that he is the Democratic presidential candidate with the best chance of unseating the GOP president.

“No disrespect to my Democratic colleagues who are competing for the nomination, they’re friends of mine, but I believe that we are the strongest campaign to defeat Trump,” he declared on Saturday to a crowd of people on the campus of Simpson College.

Sanders based his argument on what he sees as two of his key strengths.

He insists that his campaign is uniquely capable of inspiring groups of people who typically do not show up at the polls, like working-class voters and younger people.

“To defeat Donald Trump, who will be a formidable candidate for a number of reasons, we need to have the largest voter turnout in American history. That’s just a fact. If it is a low turnout election, Trump will win,” he said. “And I believe that our campaign is the campaign of energy, is the campaign of excitement [and] can bring millions of people into the political process who normally do not vote.”

Sanders also implied that his brand of economic populism makes him a more credible messenger for the idea that Trump has failed to live up to his own populist promise.

“We are going to expose his hypocrisy, his lies,” Sanders said.

“Trump said that he was a different type of Republican, that he was going to take on the establishment, he was a champion of the working class in America,” he continued. “If you’re a champion of the working class of America, you don’t try to throw 32 million people off the health care that they have! If you are a champion of working people, you don’t write a tax bill, which gives 83% of the benefits to the top 1%!”

The focus on Trump, who Sanders also characterized as a racist bent on undermining the rule of law, continues his modest shift in emphasis toward electability in the final days before the caucuses on Monday. This past Thursday, Sanders debuted a TV ad in Iowa touting his decades of experience defending Social Security from cuts, compared with Trump’s recent suggestion that he would eventually entertain reductions in “entitlements.”

But Sanders, who has occasionally struggled to keep surrogates and aides on message, also found himself implicitly addressing controversy created by Rep. Rashida Tlaib (D-Mich.) on Friday night. Tlaib, who spoke on a panel at a Sanders rally with Reps. Ilhan Omar (D-Minn.) and Pramila Jayapal (D-Wash.), joined members of the audience in booing Hillary Clinton for repeatedly attacking Sanders in recent weeks. Tlaib apologized on Saturday, but only after a spokesman for Clinton and other mainstream Democrats cited Tlaib’s conduct as an illustration of Sanders’ allegedly divisive effect on the party.

“By the way, let me say this so there is no misunderstanding,” Sanders said, “certainly I hope that we’re going to win. But if we do not win, we will support the winner and I know that every other candidate will do the same. We are united in understanding that we must defeat Donald Trump.”

Some Iowans at the rally enjoyed hearing from Sanders. Ashley Merkley, an undecided Simpson College student, who attended with her friend, Maggie Flowers, a hardcore Sanders enthusiast, said the event made it more likely that she would caucus for Sanders on Monday. She is also considering entrepreneur Andrew Yang, and Sens. Elizabeth Warren (D-Mass.) and Amy Klobuchar (D-Minn.).

“I appreciated how genuine he seemed,” Merkley said of Sanders.

Jay Wilkinson, a college employee, attended the event, despite his commitment to caucus for former South Bend, Indiana, Mayor Pete Buttigieg. He is not a fan of “Medicare for All,” which is part of why he thinks Sanders is “too far left.”

Wilkinson still appreciated hearing Sanders’ remarks, particularly his promise to support the eventual Democratic presidential nominee, regardless of who it is.

“I was very heartened by what he said today. I hadn’t heard that,” he said. “And I did hold some resentment toward him because I feel like he and his supporters lost the 2016 election because they did not get behind Hillary.”