Voters lined up across battleground Wisconsin to cast their ballots Tuesday on the first day of early in-person voting, as former President Barack Obama and Democratic vice presidential nominee Tim Walz urged supporters in the liberal capital city to do the same.

Donald Trump lost Wisconsin by just under 21,000 votes in 2020, an election that saw unprecedented early and absentee voting due to the COVID-19 pandemic. Trump and Vice President Kamala Harris are expecting another razor-thin margin in Wisconsin, and both sides are pushing voters to cast their ballots early.

Walz, the governor of neighboring Minnesota, called Harris the underdog and encouraged voters to do all they can to get people to the polls.

“Even one or two extra votes per precinct will be enough to win this thing and send Kamala to the White House,” Walz said in Madison.

Obama, the only president to carry Wisconsin by more than a percentage point in the past six elections, said he drove to the event from Chicago after his plane was leaking oil. Obama mocked Trump, calling him “loonier” than he was in 2016.

“We know this election is going to be tight,” Obama said when urging early voting. “It’s going to be tight here in Wisconsin, its going to be tight all across our country.”

Obama was headed to neighboring Michigan later Tuesday, among the several stops the former president is making in battleground states to encourage early voting.

Voters lined up Tuesday in communities across Wisconsin, including in the liberal strongholds of Milwaukee and Madison and in conservative suburban Milwaukee communities. Hours and locations for early voting varied across the state.

Raymond Lathrop, 75, a retired truck driver, voted for Trump in Kenosha on Tuesday even though he disagrees with him on some issues.

“I didn’t vote for him to be the choir boy,” Lathrop said. “I didn’t vote for him to be the pastor of my church. I voted for him to be the president of this country. This country needs to be run like a business. And he’s a businessman.”

Maria Rodriguez, 30, said she works two jobs and likes Trump’s plan on the economy, but she plans to vote for Harris because of her support for women’s reproductive rights.

“I’m moderate but my body, my choice,” she said after voting in Kenosha. “You don’t need to be in my business.”

Trump has been highly critical of voting by mail during past elections, falsely claiming it was ripe with fraud. But this election, he and his backers are embracing all forms of voting, including by mail and early in-person. Trump himself encouraged early voting at a rally in Dodge County, Wisconsin, earlier this month.

Higher turnout from Republicans has led to breaking records for ballots cast before November in key states such as Georgia and North Carolina.

Wisconsin Democratic Party Chairman Ben Wikler said given the new push from Trump and Republicans in support of early voting, “Democrats should expect Republicans to vote in massive numbers.”

Wisconsin Republican Party Chairman Brian Schimming said Monday that Trump and Republicans have been “very clear” in their support for voting early. Schimming even put in a plug for using absentee ballot drop boxes, a method of returning ballots that Trump once opposed and that some Wisconsin Republicans still do.

Numerous Republican officeholders and candidates voted Tuesday. One of them, Republican U.S. Senate candidate Eric Hovde, said after casting his ballot at the village hall in Shorewood Hills, a Madison suburb, that early voting is part of the election process now.

Hovde encouraged others to vote early because it’s impossible to predict what might happen on Election Day.

Harris has been spending a lot of time in the “ blue wall ” states of Wisconsin, Michigan and Pennsylvania in the final weeks of the campaign, including stops in Michigan and Wisconsin on Monday. Republican vice presidential candidate JD Vance was in the conservative Milwaukee suburbs on Sunday.

Early voting in Wisconsin began Tuesday and runs through Sunday, Nov. 3. Voters do not need to give a reason for voting absentee. Ballots started being sent by mail in late September, but beginning Tuesday voters can request one at designated voting locations and cast their ballot in person.

As of Monday, more than 360,000 absentee ballots had already been returned in Wisconsin. Voters can continue to return them by mail, in person, or at absentee ballot drop boxes in communities where those are available. All absentee ballots must be received by the time polls close at 8 p.m. on Election Day.

The Wisconsin Elections Commission, the agency that oversees elections in the state, said ballot processing went slowly Tuesday due to lags in the system some clerks use to print labels that they affix to in-person ballot envelopes. The commission attributed the delays to higher-than-expected turnout but staff worked to increase the system’s capacity.