U.S. President Joe Biden, who announced Sunday that he would not seek reelection in this year’s presidential race, has served in Washington for nearly half a century — in the Senate, as vice president and, lastly, in the Oval Office.

When Biden leaves the White House in January, he will have spent almost his entire career in national politics. Turning 82 in November, Biden will have been in public life longer than some of his Democratic colleagues have been alive.

Questions about Biden’s age have bookended his Washington career.

In 1972, he surprised Democrats by winning a long-shot Senate race at the age of 29, becoming the sixth-youngest senator in American history. Now his advancing age is one of the key reasons that led Democratic leaders to urge him to withdraw from the November presidential race, with polls showing that most Americans believe he is too old to serve another presidential term.

Biden’s decades as a public elected official have led to a long record of both career successes and setbacks. Here is a look at key moments in his career.

Presidential years

Biden’s years as president were marked by numerous global challenges, among them the grueling COVID-19 pandemic, the Russian invasion of Ukraine, a newly emboldened China and the economic and social fallout of all of those.

Domestically, Biden struggled to address rising inflation — the highest in four decades — that sharply boosted the cost of living for Americans, as well as deal with rising migration along southern U.S. border and issues of social, racial and gender justice.

Biden, as a presidential candidate in 2020, promised to restore civility to the White House after former President Donald Trump’s administration, marked almost daily by his vitriolic tweets targeting Democrats, his political foes in the Republican Party and the national news media. Biden pledged to work across the political divide in Congress to achieve legislative success.

To an extent, Biden was successful, winning a smattering of Republican votes for key pieces of legislation to spend billions of dollars to repair the country’s aging and deteriorating roads and bridges, promote the American production of computer chips, and install new gun controls — the first enacted in nearly three decades in the United States.

In separate legislation, Democrats, over unified Republican opposition, approved a coronavirus economic relief bill and later, a $369 billion plan to help control the effects of climate change, the biggest such U.S. allocation ever to help protect the environment.

The substantial government spending, however, has proved problematic, with some economists blaming it for the rampant increase in U.S. consumer prices that have yet to totally recede.

In perhaps his biggest foreign policy achievement, Biden led a coalition of Western nations that sent billions of dollars’ worth of armaments to Ukraine to help Kyiv’s military fend off Russian forces that had initially been expected to overrun the capital within days of their February 2022 invasion. However, even with Biden’s unwavering support, the war has become a stalemate with no easy end in sight.

Also on the foreign front, Biden’s approval ratings declined sharply after 13 U.S. soldiers were killed in the withdrawal of U.S. and allied forces from Afghanistan.

The Israel-Hamas conflict also led to challenges for Biden, who stood by Israel even after pro-Palestinian protests erupted on U.S. college campuses. As the war has dragged on, now in its 10th month, Biden has called for it to end and has grown critical of Israeli Prime Minister Benjamin Netanyahu’s conduct of the conflict.

Vice presidency

Before Biden ran for the White House in 2020, he was a top adviser to President Barack Obama during his eight years as vice president, beginning in 2009.

Biden was put in charge of many large projects, including the withdrawal of U.S. troops from Iraq and the distribution of hundreds of billions of federal dollars to state and local governments to help the economy recover from the Great Recession, as well as working closely with then-Senate Minority Leader Mitch McConnell to avoid government shutdowns and debt defaults.

When Obama surprised Biden in 2017 with the nation’s highest civilian honor, the Presidential Medal of Freedom, Obama described him as “the best vice president America’s ever had.”

The two men were famously affectionate, chronicled in countless internet memes, and their families were also close, including a friendship between first lady Michelle Obama and second lady Jill Biden as well friendships between Obama’s daughters and Biden’s granddaughters.

Obama chose Biden as his vice presidential running mate in large part because of Biden’s long experience on the international stage as a U.S. senator, which Obama hoped would balance his own limited experience in that area.

Biden was long thought of as a possible successor to Obama, but he did not run for president in 2016, citing his family’s grief following the death of his son, Beau, from brain cancer at the age of 46. However, reporting in 2019 by The New York Times said Obama had discouraged Biden from running for president in 2016 because he believed then-front runner Hillary Clinton had the best chance of winning the general election.

Senate years

After Biden won his Senate race to represent Delaware in 1972, he spent the next 36 years in the chamber, commuting by train most days over a hundred miles between Wilmington and Washington. He rose through the Democratic ranks and twice served as the head of the powerful Foreign Relations Committee and once as the chairman of the coveted Senate Judiciary Committee.

Known as someone who could work across the aisle with Republicans such as John McCain and Chuck Hagel, Biden had always advocated for bipartisanship. However, despite his ties with Republican lawmakers, he struggled to parlay his relationships into legislative successes when he came to the Oval Office.

Biden’s successes in the Senate included sponsoring the Violence Against Women Act, which made it easier to prosecute domestic violence, sexual assault, dating violence, and stalking. He was also instrumental in helping to pass the Brady Bill, which required background checks for the purchase of most firearms.

Critics say that in retrospect, some of his votes were failures. Biden has expressed regret for several of his Senate decisions, including supporting the 1994 crime bill that contributed to higher incarceration rates of African Americans and his vote to authorize the invasion of Iraq in 2003.

He was also criticized for his role as chairman of the 1991 confirmation hearings for Supreme Court justice Clarence Thomas, who was accused of sexual harassment by Anita Hill. In 2019, Biden offered an apology — not his first — about the situation, saying “To this day, I regret I couldn’t come up with a way to get [Hill] the kind of hearing she deserved.” Hill and her supporters have blamed Biden for not doing enough to protect her from being vilified during the hearing.

Presidential runs

Before his successful presidential run in 2020, Biden had twice earlier run for the presidency, failing in 1988 and 2008, to gain the nomination of his Democratic party.

He eventually won the national election in 2020 against Trump, who has refused to recognize Biden’s victory and continues to claim falsely that he was cheated out of reelection by voter fraud and vote-counting irregularities. Biden won the election by narrowly capturing several political battleground states to win the Electoral College by a 306-232 margin, the same total that Trump declared was a “landslide” when he won the presidency in 2016.

Biden won 7 million more votes than Trump, but U.S. presidents actually win office in state-by-state elections, with the most populous states having the most votes in the Electoral College and thus the most sway in the determining the national outcome.

When he took office as president on January 20, 2021, Biden, at 78, became the country’s oldest chief executive, surpassing Trump, who was 70 when he entered the White House in 2017.