(CNN) Fresh off his own primary win, Jamaal Bowman on Thursday endorsed another progressive challenger, Cori Bush, in her race to unseat a 10-term incumbent in Missouri.
Rep. William Lacy Clay and his father, former Rep. William Clay Sr., one of the founders of the Congressional Black Caucus, have represented the St. Louis district for more than 50 years. This is Bush's second time challenging Clay, who won the nomination in 2018 with nearly 57% of the vote.
Though still an underdog, Bush is better known now and has raised more money than she did two years ago. She has raised nearly $500,000 overall, with almost half of it coming in during the second quarter of 2020, according to her campaign. Bowman's endorsement, his first since securing victory over Engel, comes less than two weeks before the August 4 primary. If Bush were to win, the result would be another blow to the Democratic Party establishment on Capitol Hill, which has now seen stalwarts like Engel and former Rep. Joe Crowley of New York lose to insurgent progressive candidates in successive primary cycles.
"Cori Bush is exactly what Missouri needs right now, what St. Louis needs, what Ferguson needs, what this country needs," Bowman said in an interview. "I mean, talk about someone who's been through it: Cori Bush is a single mother of two, she's been homeless, she's a pastor, she's a registered nurse. And she was there on the front lines during the uprising in Ferguson, which is the epicenter and the beginning of the Black Lives Matter movement."
In a statement, Bush drew a parallel between her campaign and those run by Bowman and other progressive challengers, who have accused incumbent rivals of becoming disconnected from their constituencies after long spells in office.
"Jamaal Bowman's decisive victory in New York shows the power there is in running as candidates who are deeply rooted in our communities," Bush said. "I'm so proud to have Jamaal's endorsement and to stand shoulder to shoulder with him on a platform that will transform life for the regular, working people of our districts and all over the country. From St. Louis to New York City, our communities have lived through generations of struggle, and now it's our time to build a better future that works for us all. It's our time to make history."
Bowman, whose own race was called less than a week ago, wasted little time in jumping back into the fray.
"We don't have time to relax, take a break or rest," he said. "We've got to get in the game and we've got to support others that we believe in."
Earlier this week, Engel, after conceding to Bowman, told CNN he believed that primary challenges are a "very dangerous thing for party unity" and suggested the Democratic caucus would have difficulty functioning "if there are people sitting right in there who want to get you defeated."
Bowman laughed off the suggestion.
"We don't worry about who we're going to offend when we serve in the caucus," he said. "Our job is to serve the people in our district, specifically, and the American people, more generally. It's about getting things done. So we need to remain focused on getting things done, regardless if that upsets someone."
In 2018, Bush received the backing of Rep. Alexandria Ocasio-Cortez, who had won her primary over Crowley, then the fourth-ranking Democrat in the House, less than six weeks earlier. Ocasio-Cortez, who has generally taken a more cautious path on endorsements this year, is sitting out the rematch. Last February, Clay posted a picture of the pair smiling together in a press release announcing he would co-sponsor a Green New Deal resolution from Ocasio-Cortez and Massachusetts Sen. Ed Markey.
But the Democratic Party's insurgent left wing has kept up the electoral pressure, targeting deep blue districts like Clay's in a bid to add to their sway -- and whip count -- in the House majority. Justice Democrats, the progressive group that launched Ocasio-Cortez's first campaign, backed Bowman in New York and endorsed Bush, for whom they've raised more than $40,000, among others.
Bush also has the support of Vermont Sen. Bernie Sanders, who had mostly shied away from getting involved in primary races against his Democratic colleagues before this year. In 2020, though, he has been more aggressive and willing to publicly oppose incumbents and party leadership's picks.
In June, he endorsed six House and Senate primary candidates, including Bowman and Bush. Others, like Mike Siegel in Texas and Mondaire Jones in New York, won their primaries.
Kentucky state Rep. Charles Booker, widely viewed as a longshot going into the final months of his campaign, lost narrowly to party-backed fundraising giant Amy McGrath in the contest to take on Senate Majority Leader Mitch McConnell in November.