Republican Sen. Roy Blunt of Missouri will not seek a third term in the U.S. Senate, he said Monday in a surprise announcement.

Blunt, who turned 71 in January, was widely expected to seek a third term in 2022. Before election to the Senate he served seven terms in the U.S. House. He also served two terms as Missouri's secretary of state from 1985 to 1993.

“In every job Missourians have allowed me to have, I’ve tried to do my best,” Blunt said in his announcement made via video. "In almost 12,000 votes in the Congress, I’m sure I wasn’t right every time, but you really make that decision based on the information you have at the time.

“After 14 General Election victories — three to county office, seven to the United States House of Representatives, and four statewide elections — I won’t be a candidate for reelection to the United States Senate next year," he said.

Blunt is the No. 4 in Senate Republican leadership and is the fifth Senate Republican to decide against running for re-election in 2022. The others are Pat Toomey of Pennsylvania, Rob Portman of Ohio, Richard Shelby of Alabama and Richard Burr of North Carolina.

After a failed gubernatorial bid in 1992, Blunt was elected to the House in 1996 and re-elected six times, winning by wide majorities each time. He was House majority whip from 2003 to 2007.

After incumbent Republican Sen. Kit Bond announced his retirement in 2009, Blunt ran for the vacated seat and defeated Democrat Robin Carnahan by a 54% to 41% vote in 2010. He narrowly won reelection in 2016, defeating Democrat Jason Kander by less than 3 percentage points.