Gov. Nikki Haley speaks at the 2016 Kemp Forum on Expanding Opportunity in Columbia, South Carolina, Jan. 9, 2016. Reuters/Randall Hill

UPDATE: 6:28 p.m. EST -- South Carolina Gov. Nikki Haley endorsed Florida Sen. Marco Rubio Wednesday night at an event in Chapin, South Carolina, just days before the Palmetto State’s Republican primary.

"If we elect Marco Rubio, every day will be a great day in America," Haley said, CNN reported. "I wanted somebody with fight, I wanted somebody with passion, I wanted somebody who had the conviction to do the right thing, but I wanted somebody humble enough to remember he works for all the people.”

Original story:

Florida Sen. and Republican presidential candidate Marco Rubio is set to score a major endorsement from South Carolina Gov. Nikki Haley. The State newspaper in Columbia reported that Haley is expected to announce her support for Rubio at a rally Wednesday evening.

The Post and Courier newspaper in Charleston also reported that the governor would back Rubio. Haley is a coveted endorsement for GOP candidates in the state scheduled to hold its primary Saturday. Former Florida Gov. Jeb Bush was also considered a contender to land Haley's endorsement, but the influential governor — South Carolina's most popular Republican politician in the polls — reportedly chose to go with Rubio, who is considered the top establishment candidate challenging front-runners Donald Trump and Texas Sen. Ted Cruz.

The Haley endorsement would mark another key win for Rubio, who has already been backed by important GOP South Carolina politicians Sen. Tim Scott and Rep. Trey Gowdy. The state's other U.S. senator, Lindsey Graham, meanwhile, has been campaigning for Bush.

Trump continues to lead in the South Carolina polls, garnering 35 percent support, according to the Real Clear Politics average. Cruz is polling at second with 17.8 percent, followed by Rubio (16 percent), Bush (9.8 percent), Ohio Gov. John Kasich (9 percent) and retired neurosurgeon Dr. Ben Carson (6 percent).

Haley, who endorsed eventual GOP presidential nominee Mitt Romney in 2012, had previously told reporters that she had not made up her mind about who to support in the 2016 race. Haley had spoken out, however, against Trump and has been critical of his stances on immigration. The businessman represents "everything a governor doesn't want in a president," she said.

Haley has earned attention in the national media over the past year for her response to a deadly shooting at a Charleston church, her call to remove the Confederate flag from the South Carolina Statehouse grounds and for delivering the GOP response to President Barack Obama's State of the Union address last month.

The key endorsement for Rubio comes in the South Carolina race's final days, giving Haley time to try to sway voters at the last minute. "I would love to have her endorsement," Rubio said to the Post and Courier’s editorial board Tuesday. "I’m not sure she’s going to endorse anyone."