In Arizona, Republican primary voters delivered a good showing for Ambassador Haley last night, weeks after she suspended her campaign, signaling that nearly one in five primary voters in the state are unhappy with their party’s nominee.

Arizona was the high water mark for the vote for Ms. Haley in Tuesday’s primary, with the former governor of South Carolina receiving nearly 19 percent of the vote in the state to President Trump’s 78 percent.

Arizona also holds a closed election for the presidential nomination, something they call a “presidential preference election,” and voters have to be registered with the party prior to voting in that party’s election, meaning that there were no independents skewing the GOP election’s results as has happened in other states such as New Hampshire.

A Republican strategist working on a campaign to mobilize GOP voters against Mr. Trump, John Conway, tells the Sun that “We can see these primary results as a precursor to what could happen in November.”

“I think Nikki Haley getting 18 percent of the vote in Arizona is incredibly dangerous for Donald Trump in November,” Mr. Conway says. “These voters know Nikki Haley suspended her campaign, they know that Donald Trump is the presumptive nominee.”

While there was no exit polling conducted in Arizona, it’s not clear whether voters in Arizona who supported Ms. Haley will ultimately lean towards supporting Mr. Trump in the general election, switch to President Biden, or simply stay home on election day.

However, in Mr. Conway’s interpretation, the chief reason to vote for Ms. Haley at this stage of the primary competition is to take advantage of “an opportunity to vote against Donald Trump.”

“When you look at Kansas, Illinois, Ohio — these are all places where Nikkie Haley is getting over 10 percent,” Mr. Conway says. “These are the same voters that the Biden campaign and the anti-Trump Republican campaign will be targeting… Donald Trump is an incredibly strong primary candidate and an extremely weak general election candidate.”

In other states, Ms. Haley also received significant support in the GOP primary. In Kansas, she received 16 percent support. In both Ohio and Illinois, she received about 14 percent of the vote.

The Arizona results, however, may be particularly concerning for Mr. Trump’s campaign, given that Mr. Biden defeated Mr. Trump in the state by just more than 10,000 votes.

A chief speechwriter of President Bush, Marc Thiessen, appears to agree with Mr. Conway, telling Fox News last week that “What Trump needs to understand is that MAGA voters are not going to decide this election.”

“Trump has to win them over, he has to pivot now to the general election and focus on uniting the party and the non-MAGA part of the GOP,” Mr. Thiessen said. “The Haley voters are the swing voters of the 2024 election.”

While the battle to woo supporters of Ms. Haley is already well underway, Mr. Biden’s campaign may be winning the battle to win over Ms. Haley’s financial backers.

Mr. Trump has scorned Ms. Haley’s backers despite his recent cash crunch, saying that “Anybody that makes a ‘Contribution’ to [Haley] from this moment forth, will be permanently barred from the MAGA camp. We don’t want them, and will not accept them.”

On the other hand, Mr. Biden has said “I want to be clear: There is a place for them in my campaign.” It appears that Mr. Biden’s tactic has produced results.

CNBC reports that at least a half dozen major financial backers that once raised money on behalf of Ms. Haley are now working to raise money for Mr. Biden.