Why Nikki Haley Has So Few Friends Left in South Carolina Politics

An official with Mr. Trump’s campaign in South Carolina, who spoke on the condition of anonymity, denied arm-twisting was involved, saying legislators were simply encouraged to ride a political wave for Mr. Trump.

On Wednesday night, as Ms. Haley spoke to a boisterous crowd in North Charleston, the Trump campaign blasted out its newest list of endorsements in South Carolina, 158 names in all, including both senators, five out of six Republican House members, the governor, lieutenant governor, attorney general, treasurer and many state lawmakers.

For some, putting their name on the list was likely pure politics, not animus toward Ms. Haley. Josh Whitley, a county commissioner in the Charleston suburbs and an ally of Ms. Mace, said the congresswoman’s endorsement of Mr. Trump was pragmatic. Mr. Trump is going to be the eventual nominee, he said. The former speaker of the House, Kevin McCarthy, is scouring her district, looking for a conservative to challenge her in the primaries as payback for her role in deposing him. She couldn’t afford to have Mr. Trump working against her as well.

Ms. Mace would not confirm that reason. She simply said, “South Carolina likes Nikki Haley, but they love Donald Trump.”

Other missed or tardy endorsements from her former allies stand out.

Mark H. Smith, a Berkeley County state representative and Charleston funeral home executive, served on Ms. Haley’s “grass roots steering committee” for her re-election bid in 2014. He went to high school and the junior prom with Ms. Haley. He has spoken fondly of their youth together, riding bikes around the small town where she grew up, Bamberg, S.C.

He is one of the 158 names on Mr. Trump’s endorsement list.

Jazmine Ulloa contributed reporting. Kitty Bennett and Susan C. Beachy contributed research.