Pennsylvania’s Republican Senate contest, the biggest and most expensive race of a five-state primary night, is a photo finish between David McCormick, a former hedge fund executive, and Dr. Mehmet Oz, the celebrity surgeon. It appears headed to a statewide recount.

The night delivered a split decision for former President Donald J. Trump, with his choice for Idaho governor falling well short, Dr. Oz in a virtual tie and his candidates for Senate in North Carolina and governor in Pennsylvania triumphant.

On the Democratic side, voters pushed for change over consensus, nominating a left-leaning political brawler for Senate in Pennsylvania and nudging a leading moderate in the House closer to defeat in Oregon as votes were counted overnight.

Here are a few key takeaways from Tuesday’s primaries, the biggest day so far of the 2022 midterm cycle:

Republican voters mostly rewarded candidates who dispute the 2020 election results.

The Republican candidates who did best on Tuesday were the ones who have most aggressively cast doubt on the 2020 election results and have campaigned on restricting voting further and overhauling how elections are run.

Doug Mastriano, the far-right candidate who won the G.O.P. nomination for Pennsylvania governor in a landslide, attended the rally on Jan. 6, 2021, that led to the assault on the Capitol and has since called for decertifying the results of the 2020 election.

Representative Ted Budd of North Carolina, who beat a former governor by over 30 percentage points in the state’s Republican primary for Senate, voted last year against certifying the 2020 election results — and, in the aftermath of that contest, texted Mark Meadows, then the White House chief of staff, to push the bogus claim that Dominion Voting Systems might have had a connection to the liberal billionaire George Soros.

On Tuesday, Mr. Budd refused to say that President Biden was the legitimate 2020 victor.

Voters in Pennsylvania’s Republican primary for Senate sent a more mixed message: Kathy Barnette, a far-right commentator who centered her campaign on Mr. Trump’s election falsehoods, trailed her narrowly divided rivals Mr. McCormick and Dr. Oz early Wednesday.

But Ms. Barnette, with roughly 25 percent of the vote, performed far better than many political observers had expected just two weeks ago, when she began a last-minute surge on the back of strong debate performances.

Mr. McCormick and Dr. Oz are hardly tethered close to reality on election matters. Both have refused to acknowledge Mr. Biden as the rightful winner in 2020, playing to their party’s base of Trump supporters.

The success of the election deniers comes after a year and a half in which Mr. Trump has continued to fixate on his 2020 loss and, in some places, has called on Republican state legislators to try to decertify their states’ results — something that has no basis in law.

The G.O.P. will feel bullish about the Pennsylvania Senate race. The governor’s contest is another story.

Republicans avoided what many saw as a general-election catastrophe when Ms. Barnette, who had a long history of offensive comments and who federal records show had finished ninth in the fund-raising battle in Pennsylvania’s Senate race, slipped far behind Mr. McCormick and Dr. Oz.

Both Mr. McCormick, a former hedge fund executive, and Dr. Oz, who was endorsed by Mr. Trump, have largely self-financed their campaigns and could continue to do so, though neither would have much trouble raising money in a general election.

The eventual winner will face Lt. Gov. John Fetterman, a Democrat who has long been a favorite of progressives but has recently tacked to the center as his primary victory became assured.

With nearly all of the vote counted, the margin between Mr. McCormick and Dr. Oz was well under one-half of one percent, the threshold to trigger automatic recounts for statewide races in Pennsylvania. Before that can happen, thousands of mailed-in votes are still to be counted from counties across the state.

Whoever emerges from the Republican Senate primary will be on a ticket with, and will probably be asked to defend positions taken by, Mr. Mastriano. He has run a hard-right campaign and enters the general election as an underdog to Josh Shapiro, the state’s Democratic attorney general.

Trump’s endorsement is still worth a lot. But Republican voters often have minds of their own.

In Ohio this month, J.D. Vance received 32 percent of the vote. In Nebraska last week, Charles W. Herbster got 30 percent. And on Tuesday alone:

• Dr. Mehmet Oz was hovering around 31 percent of the vote in Pennsylvania.

• Bo Hines took 32 percent in a House primary in North Carolina.

• Lt. Gov. Janice McGeachin of Idaho lost her primary for governor with about a quarter of the vote.

All of these candidates were endorsed by Mr. Trump in competitive primaries. And the outcome of these races has established the value of his endorsement in 2022: About one-third of Republican primary voters will back the Trump candidate.

In some races, like Mr. Vance’s for Senate and Mr. Hines’s, that’s enough to win and for the former president to claim credit. Elsewhere, as in Mr. Herbster’s bid for governor, the Trump-backed candidate fell short.

To be sure, Mr. Trump has won far more races than he has lost, and he saved face on Tuesday night with his late endorsement of Mr. Mastriano as polls showed the Pennsylvania candidate with a strong lead.

Mr. Trump’s early endorsement of Mr. Budd in North Carolina’s Senate race choked off support and fund-raising for Mr. Budd’s establishment-minded rivals, including former Gov. Pat McCrory.

But in Nebraska, Mr. Herbster and Mr. Trump couldn’t compete with a local political machine and millions of dollars from Gov. Pete Ricketts. In Pennsylvania, some local Republicans never warmed to Dr. Oz despite the Trump endorsement.

None of this bodes well for Mr. Trump’s Georgia picks, who are facing cash disadvantages and, unlike in the primary contests so far this year, entrenched incumbents. The Georgia primaries are next week.

Conor Lamb said electability matters most. Voters agreed — and chose John Fetterman.

When he burst onto the national political scene in 2018 by winning a special election to a House district Mr. Trump had carried by 18 points, Conor Lamb presented himself as the Democrat who could win over Republican voters in tough races.

Mr. Lamb made electability his central pitch to Pennsylvania voters in this year’s Senate race. Democratic voters didn’t disagree — they just decided overwhelmingly that his opponent, Mr. Fetterman, was the better general-election choice in the race.

Mr. Fetterman, who left the campaign trail on Friday after suffering a stroke and had a pacemaker installed on Tuesday, outclassed Mr. Lamb in every aspect of the campaign.

The lieutenant governor raised far more money than Mr. Lamb, even though the congressman employed the same fund-raising team used by Senator Chuck Schumer, the Senate majority leader. Mr. Fetterman’s muscular liberal agenda also energized more voters than Mr. Lamb, who, from the day he entered Congress, distanced himself not only from Democrats’ left wing but also from Speaker Nancy Pelosi, whom he refused to back as the party’s leader.

In the end, Mr. Lamb turned out to be perfect for the resistance-era Democrats of 2018 and 2020, when primary voters took a win-at-all-costs posture. But now that the party controls Congress and the White House, Pennsylvania Democrats decided to go with a candidate they viewed as more of a fighter.

Progressives had a good night elsewhere, too: In Oregon, Representative Kurt Schrader, a veteran Democratic centrist, was trailing badly to a left-leaning opponent, Jamie McLeod-Skinner. She had hit Mr. Schrader, who was endorsed by Mr. Biden, for voting against key elements of the Democratic leadership’s policy agenda.

Madison Cawthorn found out the hard way that voters have a limit.

Two years ago, Representative Madison Cawthorn burst into Congress like a rocket, winning an upset victory over a Trump-endorsed candidate in a primary for his western North Carolina district and became an instant national media sensation.

On Tuesday, he lost his primary and left his election-night party without giving a concession speech.

In the end, even the Trump-friendly Republican voters of western North Carolina had had enough. The flurry of embarrassing videos from Mr. Cawthorn’s personal life, which emerged after he angered fellow Republicans with wild claims that members of Congress had used cocaine and held orgies, turned out to be too much.

This wasn’t an instance of Republicans choosing electability over a firebrand. Mr. Cawthorn was in little danger of losing a general election, though Democrats would have thrown a ton of money against him to try.

Instead party leaders, in both Washington and North Carolina, sought to rid themselves of a problem child in their midst by coalescing around Chuck Edwards, a state senator backed by Senator Thom Tillis and an array of other North Carolina Republicans.

The defeat for now ends Mr. Cawthorn’s brief political career, which began with the promise of being the youngest person ever elected to Congress.

Now, at age 27, he is left with an enormous social media following and potentially lucrative career opportunities outside electoral politics.