Rep. Jake Auchincloss advanced in the Massachusetts 4th Congressional District race, facing off against challenger Jason Poulos. Auchincloss, who has held the seat since 2021, faced his first Democratic primary challenge since taking office.

Poulos, an AI policy researcher, criticized Auchincloss’s past support for military aid to Israel and his connections to AIPAC. Poulos advocated ending U.S. military assistance to Israel, reflecting his progressive stance. His campaign focused on issues like Medicare-for-all, universal basic income, taxes on corporate automation, and student debt cancellation. Additionally, he pushed for reduced military spending.

Auchincloss, endorsed by AIPAC, has been critical of certain Israeli actions in Gaza. He acknowledged some Israeli measures in 2025 crossed humanitarian lines. AIPAC, a pro-Israel lobby, has received criticism for supporting U.S. military aid to Israel amid the Gaza conflict.

In a significant move, Auchincloss voted with more than 100 House Democrats in July to eliminate $3.3 billion in U.S. military financing for Israel. Despite this, he continues to support the U.S.-Israel alliance. His campaign emphasized lowering housing and healthcare costs, fostering economic growth, and preparing Democrats to handle AI-related economic disruptions.

Auchincloss’s background includes succeeding Joe Kennedy III and coming from a well-known Boston medical family. Previously a registered Republican, he worked on former Governor Charlie Baker’s campaign. His shift back to the Democratic Party has been highlighted by his opponents.