Marco Rubio presidential campaign, 2016 declared he was running for president approximately three weeks after this fellow republican who has served  as the junior United States Senator from Texas since what year
Ted Cruz Rafael Edward Cruz ( ; born December 22, 1970) is an American politician and attorney who has served as the junior United States Senator from Texas since 2013. He was a candidate for the Republican nomination for President of the United States in the 2016 election.
Johnny Isakson John Hardy Isakson (born December 28, 1944) is the senior United States Senator from Georgia, in office since 2005, and a member of the Republican Party. Previously, he represented  in the United States House of Representatives from 1999 to 2005.