Rep. Trey Gowdy officially threw his weight behind Sen. Marco Rubio's presidential campaign Tuesday by joining him on the road in Iowa for a two-day trip to close out 2015.

"I'm in Iowa to give you a word of encouragement," Gowdy started. "It is not my job to tell you who to vote for. But I am going to tell you who I'm going to vote for ... I'm going to vote for Marco Rubio."

Gowdy explained to the crowd that national security and public safety was his determining factor, saying there is "no one better" than Rubio on those two issues.

"I trust Marco Rubio to lead a country safely that has the three most precious things in my life in it," Gowdy said, pointing to his wife and two children, "which is the United States of America over the next four to eight years."

"I've found my candidate: It's Marco Rubio," Gowdy concluded.

Gowdy is best known as the chairman of the House Select Committee on Benghazi, which has led the effort into finding out who was at fault for the Benghazi terror attacks on Sept. 11, 2012.