Rubio also backed away from the day-to-day responsibilities of representing Florida in the U.S. Senate. Between April 2015 and March 2016, he missed 65 percent of Senate votes, according to Politifact. He defended himself by arguing that running for president is a full-time job. True, but so is representing Florida in the U.S. Senate. Yet in his current re-election campaign, he has pointedly refused to rule out another presidential bid in 2020.