Centrist Democrats claimed victory Wednesday over the progressive wing of the party after socially conservative Rep. Dan Lipinski, D-Ill., narrowly won his primary in the 3rd District of Illinois.

The bipartisan group No Labels took credit for Lipinski's success, revealing that they threw $1 million behind the incumbent.

Seen as a microcosm of the ongoing battle between the centrist and progressive wings over the soul of the Democratic Party, the race attracted a large number of national outside groups. Three of Lipinski’s Democratic House colleagues and Sen. Bernie Sanders, I-Vt. backed his challenger, businesswoman Marie Newman. NARAL Pro-Choice America and EMILY’s List also joined the onslaught against the seven-term congressman.

Newman closed the considerable 30-point gap, hitting Lipinski for his positions against abortion rights and same-sex marriage, but came up short by 1,600 votes.

“The Center strikes back,” No Labels declared, branding Sanders and the progressive groups that backed Newman, the “Tea Party of the Left.”

Former Sen. Joe Lieberman, national co-chair of No Labels, boasted the political center “is alive and well.”

The race brought tensions within the party to a head, as moderate Democrats warned against purity tests and liberals put centrists on notice about their vulnerability to primary challenges. Wednesday morning the feud continued on Twitter, as No Labels touted their role in helping re-elect Lipinski.



This was a targeted mission by the far left to mandate that every candidate fall into lockstep with the Bernie Sanders wing of the party. /4 — No Labels (@NoLabelsOrg) March 21, 2018

Ari Rabin-Havt, senior adviser to Sanders, shot back. "So if there is any doubt, No Labels is an anti-DREAMER, anti-LGBTQ, and anti-abortion organization. Thank you for making that clear," he tweeted.

Jon Favreau, former speechwriter for President Barack Obama, piled on, pointing out that Lipinski’s vote against the Affordable Care Act and opposition to same-sex marriage are far from where the majority of Democrats stand.

“To call people who disagree with those positions the far left is a fucking embarrassment,” Favreau added.

Through the super PAC United for Progress, No Labels and aligned group Country Forward poured half of their $1 million toward TV ads in the district and the other half toward mailers, and direct voter contact. Chicago-area mega donors have contributed hefty sums to the No Labels aligned-groups, according to the Chicago Sun Times.

Progressives hammered Illinois House Speaker Michael Madigan, a longtime ally of Lipinski and leader of the state party. "In Chicago, machines are gonna machine — but fortunately, that will not be true in most Democratic primaries this cycle," the Progressive Change Campaign Committee said in a statement.

Neil Sroka, spokesman for the progressive Democracy for America, gave No Labels and Madigan credit, saying they “definitely” played a key part in boosting Lipinski.

“The dwindling corporate wing of the Democratic Party is going to crow about this race because they have very few other races to crow about,” Sroka said. “The fact is that the growth in the party is among inclusive populist Democratic candidates.”

Sroka vowed that come 2020, Lipinski and Democrats like him will face challenges again. “Despite Dan Lipinski getting over the finish line his time is up in the Democratic Party," he said.

Where it can, however, No Labels will attempt to shield centrists, especially those who belong to the Problem Solvers Caucus, inspired by the No Labels mission to find bipartisan solutions. The caucus includes 48 members evenly split between Republicans and Democrats.

Ryan Clancy, chief strategist for No Labels, said Lipinski’s race was just the beginning.

If a moderate Democrat or Republican is being primaried, No Labels will help them. If there’s a chance to elect a future “problem solver” in an open seat, No Labels will help them. And if a “radical right or left wing incumbent who has no interest in working across the aisle” is being primaried by a centrist candidate, Clancy said, No Labels might step in.

But No Labels wouldn't share which primaries or general election races they plan to engage in until after each one concludes.