Sen. Mitch McConnell, the longest-serving Senate leader in history, announced on his 83rd birthday that he will not seek re-election, ending a four-decade career in the chamber. Elected in 1984, McConnell rose to Senate Republican leader in 2007, serving through four administrations. His retirement comes as the GOP shifts away from traditional conservatism toward a party shaped by former President Donald Trump, with whom he has had a strained relationship.

On the Senate floor, McConnell called serving Kentucky “the honor of my lifetime” and confirmed that his current term will be his last. Despite his rocky history with Trump, he supported the former president’s bids in 2016 and 2020. He notably voted to acquit Trump on impeachment charges related to the Capitol riot while condemning his actions as a “disgraceful dereliction of duty.” Nonetheless, he endorsed Trump again in 2024 after he secured the Republican nomination.

Mitch McConnell has made headlines for “freezing” in a couple of press conferences.

As Senate majority leader from 2015 to 2021, McConnell made his mark on the judiciary, blocking President Barack Obama’s Supreme Court nominee in 2016 and later overseeing Trump’s appointment of Justice Neil Gorsuch. He played a key role in confirming three Supreme Court justices and 234 conservative judges, which he considers his proudest achievement. He also pushed through Trump’s 2017 tax cut, his biggest legislative win. A longtime member of the Appropriations Committee, McConnell secured significant federal funding for Kentucky.

Known as “Dr. No” during the Obama years, McConnell led opposition to much of the Democratic agenda, including an unsuccessful effort to repeal the Affordable Care Act in 2017, thwarted by Sen. John McCain’s dramatic thumbs-down vote. Under President Joe Biden, McConnell took a more pragmatic approach, backing bipartisan deals on infrastructure and semiconductor investment.

Recently, McConnell has focused on foreign policy, advocating for a strong U.S. role in global affairs, often clashing with Trump’s “America First” stance. Their biggest divide has been over U.S. aid to Ukraine, with McConnell pushing for continued support while Trump has sought to cut back.

McConnell’s staunch defense of the 60-vote filibuster helped cement its role in the Senate, despite Trump’s demands to eliminate it. His health has raised concerns in recent years, with several public freeze-ups and a fall that led him to use a wheelchair. As the GOP increasingly aligns with Trump’s MAGA movement, McConnell’s departure has long been expected. One of the few Republicans willing to openly break with Trump, he recently voted against three of his Cabinet nominees and criticized proposed tariffs.