The progressive Working Families Party is backing State Rep. Chris Rabb for Congress

The progressive Working Families Party and a coalition of allied political groups will announce Thursday that they are endorsing Philadelphia State Rep. Chris Rabb for Congress, making him the favorite among the city’s left-leaning organizations to take the open seat long held by U.S. Rep. Dwight Evans.

The Working Families Party, a labor-aligned third party that also often backs Democrats, will endorse Rabb alongside Justice Democrats, a national organization that helps elect progressives, including members of “The Squad,” the left-wing faction in Congress.

In a statement, the groups cited Rabb’s positions supporting “Medicare-for-All,” deeply affordable housing, and the abolition of U.S. Immigration and Customs Enforcement.

City Councilmember Kendra Brooks, a member of the Working Families Party and one of the city’s most well-known progressives, said in a statement backing Rabb that “it’s time we have one of our own in The Squad.”

“Rep. Rabb is one of the longest-serving progressives in Harrisburg, where he has taken on Republicans and the billionaire class to improve the lives of working people,” Brooks said. She was joined in her endorsement by Councilmember Nicolas O’Rourke, also of the Working Families Party.

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The endorsement is significant for Rabb in that the Working Families Party and Justice Democrats are deep-pocketed organizations with national donor networks. The groups could provide Rabb with a needed financial boost after he reported middling fundraising totals earlier this year and then said his former treasurer made unauthorized withdrawals from his campaign account.

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But it is unclear if or how much money each group will spend on the race in the 3rd Congressional District, which is by some measures the most Democratic in the nation. The Working Families Party has an allied super PAC that has not yet indicated whether it intends to spend money to influence the Philadelphia race.

The May 19 primary election is likely to be decisive, given that the district is overwhelmingly Democratic. No Republican filed to run.

Rabb, an anti-establishment five-term state representative who hails from Northwest Philadelphia, said in a statement that he is “proud to be building such a strong progressive coalition in this campaign.“

He was also endorsed by the Philadelphia chapter of the Democratic Socialists of America, the left-leaning political group One PA, and two South Philadelphia Democratic wards that tend to back progressives.

A similar alliance in 2017 lifted District Attorney Larry Krasner to victory and has since then boosted a handful of progressives who now hold seats in the state House, state Senate, and City Council.

Winning the congressional seat — which is open because Evans is not seeking reelection — would be one of the progressive coalition’s biggest wins yet in Philadelphia. Left-leaning organizations in the 2023 mayoral race backed former City Councilmember Helen Gym, who came in third in the Democratic primary.

Rabb’s opponents are also being supported by groups with the ability to influence the race through advertising, including super PACs, which can raise and spend an unlimited amount of money.

Ala Stanford, a pediatric surgeon running for office for the first time, is being backed by 314 Action, a national “pro-science” super PAC that has said it will spend up to $2.5 million on the race on pro-Stanford advertising. The amount is significantly more than any single candidate currently has in their campaign account.

And State Sen. Sharif Street, the former chair of the state Democratic Party, has the support of the Democratic City Committee and a politically powerful coalition of building trades unions. The same labor groups funded a super PAC in the 2023 mayoral race that was crucial for now-Mayor Cherelle L. Parker, a centrist who handily won the Democratic primary that year.

Street has also attempted to pick off support from left-leaning Democrats, including winning endorsements from Councilmember Rue Landau and State Rep. Andre Carroll, both of whom have previously received support from the Working Families Party.