Wisconsin Lt. Gov. Mandela Barnes joins crowded Senate Democratic primary

Barnes made the announcement in a video in which he touts his record and pledges to take on issues like climate change, voting rights, health care and education.

"When you stay focused on why you are running, nothing can slow you down." Barnes says as he literally runs in the announcement video. "I'm Mandela Barnes, I'm running for US Senate and I'm running for the people of Wisconsin."

A number of Democratic candidates have already announced campaigns in the Wisconsin Democratic primary, possibly complicating Barnes' path towards the nomination. The list includes Wisconsin state Treasurer Sarah Godlewski, state Sen. Chris Larson, and Alex Lasry, a businessman whose family owns the Milwaukee Bucks.

They are all vying for the chance to take on incumbent GOP Sen. Ron Johnson, who has yet to announce whether he plans to seek reelection. Johnson had previously said he would only seek two terms in the Senate. Democrats see Johnson as vulnerable if he does run, and the prospect of an open seat in Wisconsin has raised the interest in the race.

Barnes, 34, is the biggest name to enter the Democratic field to date. He, along with Gov. Tony Evers, narrowly defeated incumbent Republicans Scott Walker and Rebecca Kleefisch in 2018, helping Democrats deliver a significant rebuke to then-President Donald Trump.

In a sign of how this could get complicated for Wisconsin Democrats, Evers did not outright endorse Barnes in a statement Tuesday, instead heralding his one-time running mate and pledging to support "Wisconsin Democrats' choice to take on Ron Johnson in 2022."

"We're lucky to have strong Democratic candidates who are running to send him packing," Evers said of Johnson.

Barnes' national profile increased in 2020 after police officers in Kenosha, Wisconsin, shot Jacob Blake, a Black man. As the first Black man to be elected statewide in Wisconsin, Barnes was outspoken in the wake of the shooting, decrying Trump for planning to visit Kenosha by labeling him as "incendiary" and arguing the trip was aimed solely at "creating more division."

"The crazy part is there are a lot of people who are in office who are just finding out that this stuff is a problem," Barnes told CNN at the time. "I do feel like emotionally, I take on probably a little bit more than other people in similar offices."

The pressure on President Joe Biden and Democrats to avoid a midterm letdown is immense, especially because they only have a slim majority in the House and a 50-50 split in the Senate.

Because of that, few races in the Senate are more important than Wisconsin, one of two seats Republicans are tasked with defending in states that Biden won in 2020. The other is Pennsylvania, where there will be an open contest after Republican Sen. Pat Toomey announced he would not seek reelection.

Four races where Republicans will be on defense will be in traditional battleground states -- Florida, Ohio, Iowa and North Carolina. Meanwhile, after winning two special election in 2020, Democrats will have to defend in two races -- Georgia and Arizona. Races in Nevada and New Hampshire, two states Biden won, will also be closely watched.

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