Katherine Clark easily beat two left-wing challengers in Massachusetts’ 5th Congressional District primary, a contest that turned on Gaza, pro-Israel political money, and who speaks for the Democratic party’s future. The race highlighted big-money fundraising, pressure from advocacy groups, and a simmering split between establishment Democrats and progressive activists over foreign policy and donor influence.
Clark, who first won her seat in a 2013 special election and moved up to House Democratic Whip in 2022, cruised to victory against Jonathan Paz and Tarik Samman. Her long tenure and leadership role inside the caucus gave her a clear advantage in name recognition and institutional support. Voters in this safely blue district opted for the experienced incumbent rather than a change agent.
The primary’s debate focused hard on Gaza and the role of pro-Israel political spending, with both challengers trying to make those issues central to their campaigns. Paz, a former city councilor and organizer, and Samman, a young Harvard Law researcher and union activist, framed their challenges around accountability on foreign policy and campaign finance. That theme energized a segment of progressive voters but did not translate into enough ballots to unseat Clark.
Money told an obvious story in this race: Clark raised roughly $4.5 million, dwarfing Paz’s $88,500 and Samman’s $43,800, according to FEC filings. Those totals made it tough for insurgents to match message reach, mailers, and digital advertising in a district that covers greater Boston suburbs. Big fundraising has long been an advantage for incumbents, and this contest was no exception.
The American Israel Public Affairs Committee, known as AIPAC, has a history of supporting pro-Israel candidates and at times has contributed to Clark’s campaigns. At the same time, Clark has publicly criticized parts of Israel’s response in Gaza and faced pressure from activists demanding a tougher stance. Her nuanced position put her between hawkish backers and progressive critics who want a complete break from pro-Israel political money.
At a district event last year Clark used the word “genocide” before clarifying she was not accusing Israel of genocide, and in July she voted to cut $3.3 billion in U.S. military aid, saying Prime Minister Benjamin Netanyahu’s government had failed to meet U.S. interests and values. Those actions signaled to many voters that Clark is willing to criticize Israeli policy when she thinks U.S. values are at stake, even while maintaining broader support for Israel’s right to exist. She still backs U.S. assistance for certain Israeli defensive systems and affirms Israel as a sovereign Jewish state.
Paz and Samman repeatedly criticized Clark for accepting AIPAC-related donations while also criticizing Israeli government actions, arguing that taking the money without renouncing it showed a lack of consistency. That critique resonated with activists who worry about the influence of well-funded lobbies on elected officials. It did not, however, generate the majority support needed to push an insurgent through in this district.
Clark’s recent electoral history shows steady strength: she ran unopposed in 2024 and defeated Republican Caroline Colarusso 74% to 26% in 2022. Those margins reflect the district’s deep Democratic lean but also Clark’s personal hold on voters. For Republican observers, the result underscores how Democratic strongholds still prize incumbency and party leadership over intra-party ideological shifts.
The primary exposed a broader tension inside the Democratic coalition: elected leaders who balance strategic alliances and national security concerns versus progressive bases pushing for cleaner breaks from established donors. From a Republican viewpoint, the split makes the party easier to target in general elections if Democrats keep fighting among themselves while incumbents spend time defending their records. For now, Clark’s win keeps a top House Democrat in place and signals that establishment figures can still withstand leftward challenges in comfortable blue districts.
