The United Democracy Project, a political action committee affiliated with AIPAC, spent more than $580,000 to support Democrat Kevin Mullin in his successful bid for the House of Representatives.

A member of the state Assembly since 2012, Mullin, 52, has been elected to fill the seat in Washington being vacated by Rep. Jackie Speier after seven terms. He received 56% of the vote in his race against David Canepa, a supervisor in San Mateo County, to represent California’s 15th Congressional District.

Though both are Democrats, Mullin and Canepa were split on key issues and had differing approaches to the Israeli-Palestinian conflict, with Canepa emerging as the more left-leaning candidate.

Separately, the American Israel Public Affairs Committee donated $7,900 to Mullin’s campaign, according to Federal Election Commission filings.

“We were proud to endorse and back Kevin Mullin because of his demonstrated support for the U.S.-Israel relationship,” AIPAC spokesperson Marshall Wittmann said in a statement to J.

Mullin, who will be sworn in on Jan. 3 by the next House speaker, is taking over a district that includes most of San Mateo County and southeast San Francisco. For the past 10 years in the Assembly, he’s represented parts of San Francisco and the Peninsula, and 15 years ago, he was elected to the South San Francisco City Council, a term that included one year (2011) as mayor.

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In his race for Congress, Mullin received endorsements from Gov. Gavin Newsom, state Sen. Scott Wiener and several other local and state representatives, including Speier herself.

Earlier this year, Mullin described himself as a “pro-Israel lawmaker” to Jewish Insider, a Washington, D.C.–based publication that covers politics, philanthropy and business news with a Jewish angle.

Both candidates endorsed a two-state solution to the Israeli-Palestinian conflict. But while Canepa argues that Jerusalem must serve as the capital of “both nations,” Mullin does not believe the U.S. should dictate the terms of any future arrangement, according to Insider. Instead, he suggests that American officials can help create the conditions for an outcome that respects “the self-determination of both the Israeli and Palestinian people,” according to a lengthy position paper.

“I am extremely grateful for the support the United Democracy Project provided my campaign for Congress,” Mullin said in a statement to J. “I am proud to be representing [California District] 15 in the U.S Congress and I am deeply aware of how important the US-Israel relationship is for the security of the region. I look forward to working on these critical issues as I begin my tenure representing the people of San Mateo and San Francisco counties in Congress.”

Founded in January, the United Democracy Project describes itself as an “organization comprised of American citizens … united in the belief that America’s partnership with our democratic ally Israel benefits both countries.”

FEC filings show the AIPAC-affiliated organization spent $26.1 million to support Republican and Democratic candidates this year, with the largest chunk ($5.9 million) going to help attorney Glenn Ivey handily defeat Donna Edwards in July in a Democratic primary in Maryland. Ivey went on to win the general election on Nov. 8 with 90% of the vote against Republican Jeff Warner in the heavily Democratic district.

The super PAC also put more than $3 million toward ads attacking progressive Summer Lee in both her primary and general races for the House seat representing Pennsylvania’s 34th Congressional District. Despite that, Lee eked out a win in the Democratic primary, then cruised to a win in the general election against Republican Michael Doyle.

The UDP did not respond to a request for comment.