With a key race too close to call, here are 4 takeaways from Tuesday's primaries

Five states held primary elections Tuesday.

They once again tested former President Donald Trump's influence on the Republican side — with mixed results; President Biden looks to have suffered a loss with one of his endorsements; a key U.S. Senate race is too close to call; and a controversial congressman lost his bid for reelection.

The results are in — well, most of them. Here's some of what they tell us:

1. Waiting on Pennsylvania

The headliner state was Pennsylvania, and especially the key Senate race there. In the GOP primary, Mehmet Oz — that's celebrity TV doctor Dr. Oz — was pitted against David McCormick, a former hedge fund head who spent millions of his own money in the race, and conservative commentator Kathy Barnette.

A late surge by Barnette may have held Oz back. Oz got Trump's endorsement, but led by just over 2,000 votes over McCormick, as of noon ET Wednesday. Barnette ran as more MAGA than Trump. Trump's pick of Oz was controversial, as many in his base don't see him as truly conservative.

An automatic recount is triggered in Pennsylvania when the results are within 0.5 percentage points, which this is, meaning results won't likely be immediately known. That would be bad news for Republicans, as a recount would delay the start of the general election in this Senate race, which Democrats see as their top pickup opportunity as they try to hold on to control of the chamber.

Trump, who has repeatedly pushed baseless claims about election fraud, reportedly posted on his social media platform, Truth Social, that Oz "should declare victory. It makes it much harder for them to cheat with the ballots that they 'just happened to find.' "

The Democratic nominee, as expected, is Lt. Gov. John Fetterman, who won his primary in a landslide — despite Fetterman suffering a stroke days earlier and having a pacemaker implanted on Primary Day. This race promises to be dramatic and expensive, perhaps the most expensive in the country.

2. Trump's endorsements were a mixed bag

Trump may have gotten a big win a couple weeks ago in the Republican Senate primary in Ohio, but this week was a little different.

As noted, Oz struggled to the finish though may pull it off, but this endorsement only came after Trump had backed another candidate for this Pennsylvania seat who dropped out because of domestic abuse allegations.

His pick for governor, state Sen. Doug Mastriano, won the nomination. He's a controversial figure. He is pushing Trump's election lies and was at Trump's rally on Jan. 6, 2021, but says he left before the violent insurrection took place.

In North Carolina, Trump's pick for that key Senate race, Rep. Ted Budd, won handily. Trump had to intervene early and often in that race, as Budd faced a former governor and congressman — and even Trump's daughter-in-law, Lara, entertained running for this seat early on.

In Idaho, his firebrand pick for governor lost. Gov. Brad Little looks well on his way to reelection, despite a rising extremism on the political right in the state.

Trump's influence carried less weight, however, down the ballot in North Carolina, as the controversial freshman Rep. Madison Cawthorn was defeated.

3. Cawthorn losing shows Republicans do have a line — don't cross them.

Cawthorn landed in multiple scandals since coming to Washington, D.C. But he's far from the first controversial figure on the right. Marjorie Taylor Greene. Lauren Boebert. Paul Gosar. Matt Gaetz. And on. They and others have all said and done controversial things with fiery rhetoric and jaw-dropping comments. They've been pushed back on at times, like when Greene and Gosar spoke at an event held by a white nationalist. But they're still members of Congress, for now.

What Cawthorn did was different. Among other scandals — like twice trying to bring a gun through airport security — he crossed his own GOP colleagues. He accused them of participating in cocaine and sex parties — and that was apparently a step too far.

Still, Cawthorn came pretty close — he lost by less than 2 percentage points, or about 1,300 votes. That shows the power of the incumbency, even for a scandal-tarred freshman.

4. Biden's influence might be limited

If the results in Oregon's 5th Congressional District race are any indication, President Biden's influence over voters in his own party might not go that far.

Biden got a win two weeks ago in a congressional race in Ohio, when Rep. Shontel Brown defeated former state Sen. Nina Turner in an establishment-versus-progressive matchup. But Brown already appeared on a glide path to reelection.

And this week, longtime Oregon Democratic Rep. Kurt Schrader looks like he's headed for defeat in this newly drawn district. He was trailing attorney Jamie McLeod-Skinner by more than 20 points, as of noon ET, though only 53% of the estimated vote was in because of a printing error in one county.

Schrader is a moderate whom progressives targeted. The race split prominent members of the Democratic Party, both locally and nationally — and it could show the winds of change in the party, whose leader is unpopular nationally.

Also in Oregon, history is likely going to be made in the governor's office. Former state House Speaker Tina Kotek sailed to the Democratic nomination in this left-leaning state. If Kotek wins the governorship, she would become the first openly lesbian governor elected in the country.

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