McConnell, the longest-serving Senate party leader in U.S. history, chose his 83rd birthday to share his decision.

U.S. Sen. Mitch McConnell, who's spent decades in the nation's Capitol shaping Republican priorities, will not seek reelection when his term expires.

Mitch McConnell will end his Senate career with his most indelible mark on the nation’s federal courts and the chamber’s judicial confirmation process, a priority that changed the chamber’s rules and solidified a conservative Supreme Court for the foreseeable future.