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.