Summer Lee was one of just 37 House Democrats who cast courageous votes last Saturday against providing $14.3 billion in unconditional military aid to Israel. The Pennsylvania representative’s reason for breaking with President Biden and House Democratic leaders on the issue was sound; since last fall, she has been an ardent champion of a cease-fire to end Israeli’s assault on Gaza, which has killed more than 34,000 Palestinians—most of them women and children—and led to a crisis so severe that the enclave is now on the brink of mass starvation.

Advocates for peace and justice in the region have argued that restricting US military aid to Israel could break the cycle of violence, which escalated following the October 7 Hamas attack on Israel, and which now threatens to become a regional conflict. Lee also recognized that a “no” vote was the right response to what she has described as the “undeniably unconscionable” conditions in Gaza, even if most of her Democratic and Republican colleagues were voting “yes” for another blank check for Israeli Prime Minister Benjamin Netanyahu’s deadly agenda.

But Lee’s “no” vote came in the context of an immediate electoral reality that distinguished her from her colleagues. After having been nominated two years ago by the narrowest of margins, she faced what was supposed to be another serious Democratic primary challenge. Her opponent, local elected official Bhavini Patel, made Lee’s advocacy for a cease-fire and a new US approach to Israel and Palestine a key focus of her campaign. Aided by more than $600,000 in super PAC spending by hedge-fund billionaire Jeff Yass, Patel claimed that she would be a “strong partner to our president,” which was read by many as a reference to Biden’s support for Israel. That made Tuesday’s Pennsylvania primary election, coming just days after the aid vote, a critical test for Lee in particular and cease-fire supporters in general.

More cautious and compromising politicians might have avoided a supposedly controversial vote on the eve of a high-profile primary. But Lee went with her conscience.

And then she won her primary by a landslide.

Lee’s 61-39 victory margin was a powerful rebuke to those who imagine that progressive advocates for a cease-fire and justice for Palestinians are necessarily vulnerable in this year’s Democratic primaries.

“[There] were a lot of people who wanted to convince us that we could not be pro-peace and win in this district,” declared Lee at her victory rally Tuesday night, where she portrayed her win as a rejection of “the politics of the past” and spoke of a movement that says “we can ‘build peace from Pittsburgh to Palestine.’”

Lee’s win resulted from many factors, including the fact that she has been a highly engaged and effective member of Congress, who has focused on constituent service and bringing infrastructure money to her western Pennsylvania district. It also resulted from the former state legislator’s building of broad coalitions in the district, as well as the strong support she got from organized labor, and the Working Families Party and Justice Democrats. Local elected progressives, such as Allegheny County Executive Sara Innamorato and Pittsburgh Mayor Ed Gainey, lined up behind her. She even got something of a boost from Biden, who during a pre-primary visit to Pittsburgh included Lee’s name on a list of members of Congress “who had my back” in fights for infrastructure and other domestic priorities.

But there was no question that the Gaza issue hovered over the primary. When Lee rallied with US Representative Alexandria Ocasio-Cortez and other supporters on Sunday, much of the talk was about the threat posed by outside super Pac money to progressive Democrats who support a cease-fire. Though pro-Israel groups that made a major push against Lee two years ago did not spend heavily against her this year, pre-primary headlines still suggested that “Summer Lee’s primary puts Democrats’ divides on Israel on display” and the “‘Squad’ member’s primary tests shifting politics of Israel.”

Because the American Israel Public Affairs Committee and allied groups have talked of spending as much as $100 million to beat cease-fire backers this year, primary challenges to peace and justice advocates like Lee have for months drawn considerable media attention. And Yass’s super Pac spending against Lee offered a reminder that big money can and will flow into races where progressives, especially members of the Squad and their pro-cease-fire allies, such as US Representatives Cori Bush of Missouri and Jamaal Bowman of New York, face prominent challengers. Bowman and Bush, who joined Lee in voting against unconditional military aid for Israel on Saturday, are certainly not out of the woods in their primaries, which will take place, respectively, in June and August.

But Lee had a message Tuesday night for pundits who fret about the political consequences of casting courageous votes for peace and justice in the Middle East. Along with a video from her boisterous victory rally, the freshly renominated representative tweeted: “Opposing genocide is good politics and good policy. #CeasefireNow.”