MADISON, Wis. • Wisconsin Lt. Gov. Mandela Barnes won the Democratic Senate primary on Tuesday and will face two-term Republican Sen. Ron Johnson in what is expected to be one of the country’s most competitive races for control of the U.S. Senate.

Barnes’ top rivals dropped out of the race late last month and backed the former legislator, a sign of Democrats’ intense focus on defeating Johnson, who is one of former President Donald Trump’s most vocal supporters. The Senate is currently split 50-50, with Democrats relying on the vice president to break ties, and the Wisconsin contest is one of the few races seen as toss-ups in November.

Barnes contrasted his middle-class upbringing with the millionaire Johnson, who he said caters to special interests and wealthy donors. “Wisconsin deserves to be represented by leaders who have a firsthand understanding of the challenges they’re facing and their hopes for the future,” Barnes said in a statement Tuesday.

Johnson called Barnes the “most radical left candidate” Democrats could have chosen. “This is a contest between radical left socialism versus freedom and prosperity,” he said.

Voters also were choosing a Republican nominee for Wisconsin governor who could reshape how elections are conducted in the marquee battleground, where Trump is still pressing to overturn his 2020 loss and backing candidates he sees as allies.

Trump has endorsed businessman Tim Michels, a self-described outsider who has put $12 million into his own campaign, against former Lt. Gov. Rebecca Kleefisch, who has support from former Vice President Mike Pence and ex-Gov. Scott Walker.

The race to face Democratic Gov. Tony Evers is another proxy war between Trump and Pence, one-time partners now pursuing different futures for the Republican Party.

They also backed opposing GOP rivals in primaries in Arizona and Georgia — swing states that like Wisconsin are expected to be critical in the 2024 presidential race, when both men could be on the ballot.

Elsewhere Tuesday, voters in Vermont — the only state to never have a woman in its congressional delegation — chose a woman, Becca Balint, as the Democratic nominee for the state’s lone House seat. She is favored in the race to replace Rep. Peter Welch, who won the Democratic nomination for the Senate seat long held by Patrick Leahy, who is retiring.

In Connecticut, Republicans were picking an opponent to face two-term Democratic Sen. Richard Blumenthal.

And Minnesota Republicans chose Dr. Scott Jensen, a COVID-19 vaccine skeptic endorsed by the state GOP, to face Gov. Tim Walz.