Marco Rubio went to school on a football scholarship, and 9 other things to know about the 2016 hopeful

By ISABELLE CHAPMAN

Florida Senator Marco Rubio joined the race for 2016 Monday evening, when he said at the Freedom Tower in Miami that "I announce my candidacy for president of the United States."

Rubio enters the race behind in the polls, with roughly 5 percent of Republicans or Republican-leaning independents saying they would back him.

His biggest obstacle as he enters the race may be Jeb Bush, who is polling at 13 percent. The two share many political strengths, including connections to the Latino community (Bush's wife is born in Mexico, Rubio is a first-generation Cuban American), Florida roots and a relatively centrist stance on key issues that will help either win a general election.

Rubio has often cited Bush as a mentor and a friend, but now the two are also likely rivals for the Republican nomination. Bush will have seniority and family connections as strengths, while Rubio will be able to sell himself as the candidate offering fresh ideas to appeal to a younger generation that may have tired of Bush and Clinton-era politics.

While he's one of the younger candidates in the mix, the first-generation American is no stranger to the national political stage. He gave the GOP response to Obama's 2013 State of the Union address and Mitt Romney reportedly considered bringing him on as a vice presidential nominee for his 2012 ticket, though the spot eventually went to Wisconsin Republican Paul Ryan.

Whether he ends up as a vice president or president, the charismatic Cuban American has a rags-to-riches story to be proud of. Born into a humble immigrant family, he went to college for a year on a football scholarship and then took out loans when he transferred to another school. When he was sworn in as senator in 2011, Rubio said he owed more than $100,000 in student loans.

Click through the gallery above to learn more about the presidential hopeful.