Abortion is likely to once again be a big issue in this year's election cycle, and perhaps a winning issue for Democrats. The issue could divide Republicans, as some voters may prefer their party to focus on other issues, while others prefer candidates who promise to push for a national abortion ban. To that end, tonight we're tracking Republican primary candidates whose campaign websites use the phrase "pro-life," "sanctity of life," "right to life," "no abortion," "against abortion" or "unborn" and do not say abortion is an issue of states' rights:

Abortion remains legal, with restrictions, in Pennsylvania. It was a critical issue during the state's 2022 gubernatorial election. That year, Republicans in the state House and Senate and their candidate for governor, Doug Mastriano, promised to pass abortion restrictions, but voters elected Democratic Gov. Josh Shapiro, who supports access to abortion (and handed Democrats a bare majority in the state House as well).

Whether these candidates win or lose could tell us more about the potential battle lines on abortion in their respective districts, and in this critical swing state, for the general election.

—Monica Potts, 538

In Bucks County, just outside Philadelphia, steadfast moderate Republican Rep. Brian Fitzpatrick is facing a primary challenge from the right for his seat in the 1st District. Mark Houck is an anti-abortion activist and head of a nonprofit ministry group for Catholic men who made a name for himself as a bit of an anti-abortion martyr when he was charged with assault (but found not guilty) after shoving a 72-year-old clinic volunteer in 2021 while protesting outside a Planned Parenthood in Philadelphia. Fitzpatrick was first elected to Congress in 2016, succeeding his brother (the late former Rep. Mike Fitzpatrick). He's faced a primary challenger in every election since, but has always triumphed.

Fitzpatrick has made a reputation for himself locally and on the Hill as a moderate who keeps his distance from the MAGA right. He's got a track record of bipartisanship and moderate policy stances in Congress and refused to endorse Doug Mastriano, the GOP's far-right nominee for governor in 2022. He even snubbed Trump's visit to Bucks County earlier this month. His position on abortion has been a bit less clear — there's no mention of abortion on his reelection campaign website — though he has drawn ire from abortion rights groups. He's certainly no culture warrior like Houck, whose organization opposes "same-sex attraction disorders" and pornography, and works to shut down "sexually oriented businesses."

But whoever wins this primary isn't necessarily a shoe-in for the seat. Fitzpatrick or Houck will be going up against Democrat Ashley Ehasz. Fitzpatrick defeated Ehasz in 2022 by 10 percentage points, but the area is purple and shows signs of shifting blue — Biden won the district in 2020, and Democrats swept all five seats up for grabs in a recent local school board election. Fitzpatrick is the lone Republican in the districts surrounding Philadelphia, though his is the whitest of those collar counties and the conservative areas of the county are increasingly polarized. That could mean Fitzpatrick faces serious competition from Houck in the party primary, but Houck's far-right leanings could tilt the general election contest toward Democrats if he makes the ballot in November.

—Kaleigh Rogers, 538

Abortion is legal in Pennsylvania, but unlike in some other states, it is not constitutionally protected in the commonwealth. While it's not possible for an abortion-related constitutional amendment to appear on the November 2024 ballot in Pennsylvania, the outcome of the election could still impact abortion access in the state. Like Americans overall, Pennsylvanians are in favor of legal abortion, with 65 percent saying that abortion should be legal in all or most cases in a March GBAO/Fabrizio Lee/Wall Street Journal poll.

If the issue is salient for voters in November, that could be good news for Biden in the state: In the same survey, when asked to compare Biden and Trump on the issue, 46 percent said Biden would be best able to handle abortion, while 32 percent said Trump. Another 15 percent said neither, 3 percent said both would be equally able to handle the issue, and 3 percent were undecided.

—Mary Radcliffe, 538

In tonight's primaries, voters aren't just deciding on federal candidates for November's general election; they're also setting up the battles for control of the state House and Senate. In 2022, Democrats won the governorship, and they currently hold a one-vote majority in the House they've struggled to maintain through a series of special elections. The party is looking to expand that House majority and gain control of the Senate for a trifecta by targeting opportunities (and defending some vulnerable seats) in the purple areas of this purple state. And, of course, Republicans want to keep their Senate majority, which they've held for 30 years, and take back the House.

Republicans have a six-vote majority in the state Senate, so Democrats need to pick up at least three seats for a tie, which could be broken by Democratic Lt. Gov. Austin Davis. Half the chamber is up for election this cycle. Among the handful of key races, Democrats will be defending an Allegheny County seat and challenging Republicans for a Harrisburg-based seat that are both opening up because of retirements. In both districts, each party is holding a contested primary today and redistricting could give Democrats a boost in November. Democrats are also challenging Republican incumbents in two seats that flipped to red in 2016 and 2020; one will hold a competitive Democratic primary today between Erie County Democratic Party Chair Jim Wertz and former Sen. John Fetterman staffer Selena King.

In the House, the hot primary action will largely be on the Democratic side, as the party's more progressive and centrist flanks face off in districts around Philadelphia and Pittsburgh. In West Philadelphia, Rep. Amen Brown is defending his seat against two challengers, Sajda Blackwell, whose family has a history in area politics, and progressive community activist Cass Green. Brown ran unsuccessfully for mayor on a tough-on-crime stance, and has sided with Republicans in criticizing progressive Philly DA Larry Krasner. Elsewhere in the city, three incumbents endorsed by progressive group Reclaim Philadelphia are facing challengers of their own. And in the Pittsburgh area, state Rep. Abigail Salisbury, who stepped into U.S. Rep. Summer Lee's former seat, is facing a challenge from Ashley Comans, a progressive school board member who lost to Salisbury last year and is endorsed by Lee herself.

Tonight's results will have an effect on their party's chances to hold onto the state House majority in November, and also the direction the Democratic party may try to take should it seize a trifecta.

—Monica Potts, 538

The war between Israel and Hamas in Gaza has paved the way for some bitter Democratic primary fights in 2024. Among those most critical of Israel's actions in the conflict has been The Squad, an informal group of around nine progressive Democrats who often clash with their party's establishment. Of that cohort, Rep. Summer Lee of Pittsburgh is the first to face a contested primary in 2024 — but she won't be the last. At least four members, including Lee, have potentially significant primary opposition in part because of their vocal denouncements of Israel — although increasingly negative views of the Middle East nation's actions among the Democratic base means the conflict may not be as helpful to The Squad's challengers as some may have expected.

Should Lee survive, she would join Reps. Greg Casar of Texas and Delia Ramirez of Illinois among those who've won renomination (Casar and Ramirez faced no opposition in their March primaries). But some members with primaries later this summer may have problems, especially the two who are arguably most endangered: New York Rep. Jamaal Bowman and Missouri Rep. Cori Bush. For one thing, they've each been outraised by their leading challengers, and they both have potential scandals that could derail their reelection efforts. Last fall, Bowman pulled a fire alarm in a Capitol office building right before a vote, which resulted in him paying a fine and receiving a censure from the House. And Bush faces investigations by the Department of Justice, Federal Election Commission and House Ethics Committee into alleged misuse of funds to pay her security team, including payments to her husband as part of that team.

Beyond those two, Minnesota Rep. Ilhan Omar may be the other Squad member who could have some trouble. Two years ago, she defeated former Minneapolis City Council member Don Samuels by just 2 percentage points in the Democratic primary; now Samuels is back for a rematch, although Omar has already raised more than twice as much as the $2.4 million she'd brought in by the time of the 2022 primary>. Otherwise, there are few signs that New York Rep. Alexandria Ocasio-Cortez, Michigan Rep. Rashida Tlaib and Massachusetts Rep. Ayanna Pressley will have difficulties. Ocasio-Cortez does have a challenger, but his largely self-funded effort pales in comparison to Ocasio-Cortez's campaign war chest, while Tlaib's little-known opponents only just filed for the race and haven't reported raising any money. Pressley, meanwhile, has no primary opposition ahead of Massachusetts's May 7 candidate filing deadline.

—Geoffrey Skelley, 538