Pennsylvania Holds Its Primaries Today. Here’s What to Watch.

Pennsylvanians are heading to the polls on Tuesday, with a handful of House primary races in the spotlight.

The contest getting the most attention is the Democratic primary in the Pittsburgh-based 12th District, where Representative Summer Lee, who has been outspoken in support of a cease-fire in Gaza, is facing Bhavini Patel, who has attacked Ms. Lee as anti-Israel and outside the political mainstream.

Ms. Lee, a first-term representative who is part of the progressive “Squad” and narrowly won her primary in 2022 over a more centrist candidate, was one of the first members of Congress to criticize Israel’s actions in Gaza and call for an immediate cease-fire. That angered some Jewish voters in her district, though national pro-Israel groups like AIPAC have not gotten involved in her race, as they have in others. Ms. Patel has been vastly outraised in the contest, and the once-expected ideological battle over Israel has fizzled in much of the district.

On the other side of the aisle and the state — in the First District, in the suburbs north of Philadelphia — Representative Brian Fitzpatrick, one of the most moderate Republicans in the House, is facing a primary challenge from an anti-abortion activist, Mark Houck.

Mr. Fitzpatrick is one of a small number of Republicans representing districts that Joseph R. Biden Jr. carried in 2020. He won his last two general elections with relative ease. But if Republican voters nominate Mr. Houck — who was acquitted last year of charges that involved assaulting a Planned Parenthood volunteer outside an abortion clinic — it could make the district more competitive for Democrats, given the political potency of abortion.

Two other primaries may also set up competitive general-election