Kansas Gov. Sam Brownback on Monday became the first sitting governor to endorse Sen. Marco Rubio in the 2016 GOP presidential race.
"Marco Rubio is a true conservative who can unite the party and defeat Hillary Clinton or Bernie Sanders in the fall," Brownback said in a statement provided by Rubio's campaign.
Brownback, who previously served in the Senate before Rubio was sworn in, went on to say Rubio has a track record of "protecting life, defending religious liberty, and undoing Obamacare."
The endorsement is the first one Rubio has received from a sitting governor, though he has racked up plenty of endorsements from members of Congress and former governors. Brownback has served as governor of Kansas since 2011 and served in the Senate from 1996 until 2011.
Kansas holds its caucuses on March 1, which is Super Tuesday.
A poll conducted after CBS News hosted the GOP presidential debate on Saturday found that a plurality of debate watchers, 32 percent, believed Rubio won the debate.