South Carolina, Nevada primaries and Ohio special election: Nancy Mace, Sam Brown win

After tonight, we'll have seen downballot primaries in 26 states, and so far the only incumbent that has lost renomination is Jerry Carl, who due to redistricting had to run in an incumbent-on-incumbent battle against Barry Moore in Alabama's 1st district. With Mace's race now called in her favor and Timmons ahead by around 10 percentage points, it looks like tonight might continue the streak.

However, that's not too unusual. Based on my quick calculations, on average over the last 7 election cycles, just 8 incumbents who faced a primary challenger lost renomination, and in 4 of those 7 cycles, there were 5 or fewer incumbents that failed to secure their party's nomination.

But we may be on track to break the incumbent winning streak as early as next week, when Virginia representative Bob Good faces state senator John McGuire, a Trump endorsed challenger. Polls show that race up in the air, with two polls conducted since Trump's endorsement showing nearly opposite results. And the following week, Democrat Jamaal Bowman of New York's 16th faces a very tough challenge from Westchester County Executive George Latimer. So don't expect Jerry Carl to be the lone incumbent loser when all is said and done.

—Mary Radcliffe, 538

As Kaleigh just mentioned, South Carolina’s 3rd could go to a runoff between Burns and Biggs. It's notable that Biggs is in this because as I mentioned earlier tonight on the blog, no non-incumbent Republican women have won a nomination for a safe Republican seat in November in primaries before today's races. Biggs received a primary endorsement from VIEW PAC, one of the women's groups we are tracking that is endorsing women in primaries, this cycle. The other women's groups we are tracking — E-PAC, Maggie’s List, and Winning for Women — didn’t endorse in that primary.

We'll have to see what happens, if Biggs does make a runoff. In North Carolina's 13th District, another safely red seat, a woman, Kelly Daughtry received the most votes in the primary and qualified for the runoff, but she subsequently dropped out after Trump endorsed her runoff rival, Brad Knott.

—Meredith Conroy, 538 contributor

With Mace's win, she stands out among many Republican candidates in that she calls for rape an incest exceptions to abortion bans. Majorities of Americans support rape and incest exceptions to abortion bans, including most Republicans, but only about half the states that ban the procedure currently have them.

—Monica Potts, 538

Mace’s win is also a win for VIEW PAC, one of the GOP women’s groups we're tracking endorsements from in primaries this cycle. One of her several challengers included former state cabinet official Catherine Templeton, who was endorsed by Winning for Women.

We're keeping a close eye on GOP women's group endorsements tonight since, according to our analysis, primary endorsements from groups like Winning for Women, Maggie’s List and VIEW PAC that work to elect more Republican women to office is down this cycle, compared to last. This slow start may be why earlier this month Rep. Elise Stefanik, founder of E-PAC (the Republican counterpart to Democrat’s EMILYs List) told the National Journal’s Hotline that the group plans to work in alignment with the NRCC and party leadership to endorse more women moving forward.

—Meredith Conroy, 538 contributor