CHARLESTON, S.C. (AP) — Few have navigated the turbulent politics of the Trump era like Nikki Haley.

In early 2016, the then-South Carolina governor said she was “embarrassed” by candidate Donald Trump and decried his reluctance to condemn white supremacists. Nine months later, she agreed to join his Cabinet, serving as a key validator as Trump sought to win over skeptical world leaders and voters at home.

And shortly after Trump left the White House, Haley, whose resume by then included an ambassadorship to the United Nations, vowed not to step in the way if he ran for the 2024 Republican presidential nomination. Yet on Wednesday, she is poised to become the first major Republican candidate to enter the race against him.

“It’s going to be quite the high-wire act,” said veteran Republican strategist Terry Sullivan. “She says she’s always been an underdog. She will be again."

The 51-year-old Haley may be the first to take on Trump, but a half-dozen or more high-profile Republicans are expected to join the GOP's 2024 presidential nomination contest over the coming months. Some would-be competitors may be more popular than Haley even in South Carolina, where she lives and has established a campaign headquarters. 

Likely rivals include Sen. Tim Scott, a fellow South Carolinian and perhaps the most celebrated elected official in a state where Trump has already locked up endorsements from the governor and its senior senator, Lindsey Graham. Florida Gov. Ron DeSantis and former Vice President Mike Pence could also be formidable foes should they run, as widely expected.