MONCKS CORNER, S.C. — Nikki Haley hopes suburban voters — Republicans who haven't fallen in line with Donald Trump's MAGA movement, and some Democrats — will give her a boost in today's GOP primary in South Carolina, her home state.

Why it matters: But Haley's confronting a voter base that has changed since she left the governor's office in 2017. The state — including its suburbs, it appears — seems increasingly aligned with Trump.

Driving the news: Trump's improvement among suburban voters since 2020 has been a low-key storyline in the GOP contests so far.

• He's dominated all three contests, and in New Hampshire he won the large suburban counties that mostly went for President Biden in 2020 — counties that Haley needed to win to have any chance of an upset.
• There are signs that could be the case in South Carolina, where polls suggest Trump's leading by 30 points or more.

Zoom in: During the past two weeks, Haley has campaigned aggressively in the Charleston suburbs of Mount Pleasant and Moncks Corner, the Columbia suburb of Irmo and the Charlotte suburb of Fort Mill.

• But even as she's attacked Trump as an unstable loser, touted her record as governor and pitched herself to military families, Haley often has been met with shrugs from Republican voters.
• Many of those voters are newcomers who don't recall her time as governor or are more moved by Trump.
• Several of her events have been interrupted by Trump supporters who've shown up outside venues or shouted at her when she spoke.

Many voters seem to have moved on.

• "I don't really recall the things that she did as governor," Kori Welch, 39, of Mount Pleasant, told Axios outside an early voting site in Hanahan.
• Welch said he was a first-time voter who backed Trump, whom he credits with "increasing the buying power of the dollar and [bringing] jobs back into America."
• Haley "was OK [as governor] until she quit" to be Trump's UN ambassador, said Rick Buxton, 66, a retired fire marshal who showed up at a Haley rally in Moncks Corner wearing a red Trump cap.

Between the lines: "That's an example of how Trump has redefined the Republican Party even for suburban voters," said Dave Darmofal, a political science professor at the University of South Carolina.

• "Party identification has become such a strong predictor of attitude, even voters in the suburbs are adapting (Trump's) attitudes on trade and foreign policy," Darmofal said.
• He added that many well-educated Republican voters in suburbs also are drawn to Trump's push for tax cuts and economic policies such as taxes on imported goods.

Zoom out: Trump won suburban voters by 10 points in South Carolina four years ago, but he struggled in suburban counties nationwide.

• That's fed Haley's argument that Trump has electability issues nationally, after losing women by 15 points and independents by 13 points in 2020.

What they're saying: "I don't think Trump is going to be inherently strong in the suburbs in the general election — and if he is, it's going to be because of Biden's failure to attract them," GOP strategist Dave Kochel told Axios.

• "We've seen time and time again that Trump does not perform well with suburban women and independents," Haley campaign manager Betsy Ankney said on a call with reporters..
• "The [polling] numbers are wrong," said South Carolina state House Reading Clerk James "Bubba" Cromer, referring to surveys that have shown Trump ahead of Haley by more than 30 points in the state.
• "She is certainly not going to get humiliated by some 35 points," Cromer said.

Go deeper: Haley's Hail Mary strategy depends on open primaries.