Dr. Maxine Dexter, a physician and state representative, won a contentious Democratic primary in a liberal Oregon House seat on Tuesday with help from big-money super PACs and pro-Israel donors.

In Oregon’s 3rd Congressional District, a solid Democratic seat that includes most of Portland, Dexter, a mainstream progressive, is the prohibitive favorite to triumph in the general election. She is in line to succeed Rep. Earl Blumenauer, an avid transportation funding advocate who is retiring after representing the seat for 28 years.

Among other contenders, Dexter defeated Gresham city council member Eddy Morales and Susheela Jayapal, a former Multnomah County commissioner, ex-corporate attorney, and older sister to Rep. Pramila Jayapal (D-Wash.), chair of the Congressional Progressive Caucus.

Jayapal, the runner-up, was the preferred candidate of the activist left, garnering the endorsements of, among other high-profile progressives, Sen. Bernie Sanders (I-Vt.) and Rep. Alexandria Ocasio-Cortez (D-N.Y.).

But her outspoken views on topics like Israel’s war in Gaza and ties to the Congressional Progressive Caucus made her a target for pro-Israel donors and possibly, the deep-pocketed super PACs that gave Dexter an edge.

“Jayapal’s family connections into the Congressional Progressive Caucus have played a role in both giving her higher visibility and in potentially attracting opponents to her candidacy,” said Chris Shortell, a political science professor at Portland State University. “And those who are bringing outside money into the election are probably reflecting that dynamic.”

At the start of April, Jayapal had a cash advantage over Dexter of nearly $175,000.

Then, 314 Action Fund, a Democratic super PAC that backs scientists or candidates in adjacent professions, began spending heavily to promote Dexter. They would end up spending $2.2 million on advertising promoting Dexter.

A second, unknown group, Voters for Responsive Government, sprang up to spend $3.2 million attacking Jayapal for the Multnomah County commission’s failure to properly address the Portland area’s homelessness problem. Jayapal has laid most of the blame at the feet of the commission’s chair, who had overriding authority during her tenure, and touts housing policy reforms prominently on her campaign website.

Still, those ads might not have resonated if their critique had not been echoed by local opinion leaders.

The editorial board of the Oregonian newspaper, for example, wrote in its endorsement of Dexter that Jayapal’s years on the commission “were remarkably unaccomplished.”

By contrast, the newspaper declared that Dexter, as chair of the state House’s committee on housing and homelessness, had succeeded in “carefully navigating opposition to land use law changes in order to pass a slate of bills to boost and finance housing construction.”

Meanwhile, though Susheela Jayapal’s relationship to Rep. Pramila Jayapal is likely part of what earned her the suspicion of an anonymous super PAC and pro-Israel donors, it did not bring an accompanying windfall from the Congressional Progressive Caucus PAC. The younger Jayapal campaigned heavily for her Oregonian sister, but the CPC PAC, which has spent six-figure sums in Democratic House primaries in the past, did not endorse in the race.

The left-wing candidate was not entirely bereft of outside support in the face of a full-scale onslaught, however. The Impact Fund, a group that supports Indian-American candidates, spent nearly $160,000 in support of Jayapal’s bid.

But the outside spending for Dexter outstripped the analogous effort for Jayapal by a more than 30-to-1 margin.

In the final weeks of the campaign, Dexter also began lapping Jayapal in direct campaign fundraising. On a single day earlier this month, Dexter raised more than $200,000, of which the lion’s share came from pro-Israel donors with ties to AIPAC and, in some cases, Republican giving histories.

AIPAC, which did not publicly endorse Dexter, promptly congratulated her on Tuesday night.

“AIPAC members were proud to support Maxine Dexter in her race against an anti-Israel opponent endorsed by [Bernie Sanders], [Alexandria Ocasio-Cortez], and J Street,” the group posted on X. “Being pro-Israel is good policy and good politics!”

Some progressives have speculated that AIPAC or other pro-Israel donors are also behind the group Voters for Responsive Government, but the group claims to have raised its money starting only this month, which enables it to conceal its funders until after Election Day.

“This cycle is like the ‘Empire Strikes Back.’ This is the reaction to a bunch of progressive, pro-Palestine candidates getting elected, like the ‘Squad,’” said Connor Farrell, Jayapal’s fundraising consultant, referencing the House’s bloc of left-wing lawmakers of color. “And it shows the other side is willing to spend nearly unlimited amounts of money just in a House race.”

By the broad ideological standards of the House Democratic Caucus, Jayapal and Dexter are not that far apart.

But policy nuances often reveal the difference between a mainstream progressive like Blumenauer, whom Dexter might resemble, and an insurgent-style fighter in the mold of Ocasio-Cortez, who might model how Jayapal would have governed.

Jayapal ran as a proponent of Medicare for All, forswore corporate PAC donations, called for a permanent cease-fire early on in Israel’s invasion of Gaza, and demanded an end to U.S. funding of Israel’s military until the war ends.

Dexter, by contrast, speaks of working “toward the goal of adopting a single-payer model,” has not explicitly rejected corporate PAC donations, and is calling for a cease-fire that includes the return of the Israeli hostages. She told Jewish Insider that she would support a policy of reviewing humanitarian clauses on U.S. aid to all countries, but not a policy directed at Israel on its own.

Jayapal’s campaign insists that the support of pro-Israel donors ― and the endorsement of one group, Pro-Israel America ― foreshadows how Dexter would approach the thorny issue currently dividing the Democratic Party.

“Where the money comes from is a pretty good window into where candidates’ values are or will be, which is not necessarily what they say publicly,” Farrell said.

More importantly, the campaign and its allies highlighted some of Dexter’s pro-Israel donors ties to prominent Republicans in a bid to paint her as a stalking horse for cynical right-wing interests. One such donor was Larry Mizel, the chair of a Denver-based home-building giant, who served as finance chair on former President Donald Trump’s 2016 presidential campaign.

But 30 of Dexter’s colleagues in the state legislature, including the House speaker and Senate majority leader, rushed to her defense in a public statement.

Dexter has “earned a reputation as a principled, independent, and effective legislator. The idea that she would ever do the bidding of any group or special interest is offensive and wrong,” the group wrote.