South Carolina Gov. Nikki Haley is reportedly set to announce her endorsement of Marco Rubio for the Republican presidential nomination on Wednesday evening. Jeb Bush was considered an early favorite to earn her support after he helped her raise money for a previous re-election bid, but Rubio currently sits in third place in South Carolina—polling behind Donald Trump and Ted Cruz—and could prove a more viable candidate for moderates and conservatives looking for an alternative to the two more extreme frontrunners.