AP Photo/Paul Sancya
Rubio, the Florida senator, told supporters in the Palmetto State that he "will win the nomination."
"Practically speaking," he said, "it's down to three."
Rubio was in second place in South Carolina with 84% of precincts reporting. He was ahead of Cruz by a slim 22.3% to 21.7%, The Associated Press reported. Rubio trailed real estate mogul Donald Trump, the front-runner and South Carolina winner, by roughly 11 points.
"Tonight here in South Carolina, the message is pretty clear," he said. "This country is now ready for a new generation of conservatives to guide us into the 21st century."
Rubio began his speech by congratulating Trump. He then showered praise on former Florida Gov. Jeb Bush, who dropped out of the race on Saturday night. Bush's campaign suspension could aid Rubio by consolidating more of the Republican establishment's support around the Florida senator.
"I have an incredible affection and admiration for Gov. Bush and his family and their service to this country," Rubio said. "Jeb Bush has many things to be proud of. He's an extraordinary husband and father, he was the greatest governor in the history of Florida."
"I pray that his service to this country has not yet ended," he continued. "I pray for his family tonight as they move on to other endeavors in their life."