Joe Biden, a fixture in U.S. politics for a half century as a senator and vice president, is seeking to complete a long climb to the political mountaintop that includes two previous failed presidential bids by defeating President Donald Trump on Tuesday.
If Biden beats the Republican president, a fellow septuagenarian, the 77-year-old Democrat from Delaware would become the oldest person ever elected to the White House.
Biden has sought to portray his political experience as a benefit, casting himself as a tested leader up to the tasks of healing a nation battered by the coronavirus pandemic and providing steadiness after the turbulence of Trump's presidency.
Accepting the Democratic presidential nomination in August, Biden stressed compassion and decency, seeking to draw a contrast with the pugnacious Trump.
"I'll be an ally of the light," Biden said, "not the darkness."
Trump has derided him as "Sleepy Joe" and said his mental capacity was "shot" as the president's allies sought to portray Biden as senile.
If elected, Biden would be 78 years old upon inauguration on Jan. 20. Trump, 74, was the oldest person to assume the presidency when he was sworn in at age 70 in 2017.
Biden unsuccessfully sought the Democratic presidential nomination in 1988 and 2008 before finally securing his party's blessing this year with strong support among Black voters.
He brings to his political career a mix of blue-collar credentials, foreign policy experience and a compelling life story marked by family tragedy - the loss of his first wife and a daughter in a car crash, and a son to cancer.
Biden arrived in Washington as a young upstart. He was elected in 1972 at age 29 to the U.S. Senate from Delaware and remained there for 36 years before serving from 2009 to 2017 as vice president under Barack Obama, the country's first Black president.
Trump has sought to turn Biden's experience into a liability, denouncing him as a career politician. Trump has said Biden would become a puppet of the Democratic Party's "radical left."
The coronavirus pandemic has been front and center in the presidential race. Biden accuses Trump of surrendering in the face of the public health crisis, saying the president panicked and tried to wish away the virus rather than do the hard work needed to get it under control, leaving the economy in shambles and millions of people jobless.
Trump, who was hospitalized for three days after contracting COVID-19, has mocked Biden for regularly wearing a face mask to guard against the pathogen's spread.
'THE SOUL OF THIS NATION'
After serving as vice president, Biden opted not to run for president in 2016, only to watch Trump defeat Democrat Hillary Clinton. When Biden announced his 2020 candidacy in April 2019, he took aim at Trump.
"We are in the battle for the soul of this nation," Biden said, adding that if re-elected Trump would "forever and fundamentally alter the character of this nation - who we are - and I cannot stand by and watch that happen."
Biden selected Senator Kamala Harris - whose father is an immigrant from Jamaica and whose mother is an immigrant from India - as his running mate, making her the first Black woman and first person of Asian descent on a major-party U.S. ticket. At 56, Harris is a generation younger than Biden.
An effort by Trump to dig up dirt on Biden resulted in the president's impeachment in the Democratic-controlled U.S. House of Representatives in December 2019. The two articles of impeachment - abuse of power and obstruction of Congress - stemmed from Trump's request that Ukraine investigate Biden and his son Hunter on unsubstantiated corruption allegations.
In February, the Senate, controlled by Trump's fellow Republicans, acquitted him of the charges after refusing to call any witnesses.
U.S. intelligence agencies and the FBI director this year concluded that Russia, after interfering in the 2016 election to harm Trump's opponent Clinton, was engaging in a campaign to denigrate Biden and boost Trump's re-election chances while promoting discord in the United States.
Biden's previous two presidential runs did not go well. He dropped out of the 1988 race after allegations that he had plagiarized some speech lines from British Labour Party leader Neil Kinnock. In 2008, Biden won little support and withdrew, only to be selected later as Obama's running mate.
The folksy Biden, known for blunt talk and occasional verbal gaffes, has often referenced his working-class roots to connect with ordinary Americans. Biden also was the first Roman Catholic U.S. vice president.
Under Obama, Biden served as a troubleshooter on matters of war and foreign affairs and on domestic issues such as gun control and fiscal policy.
Obama did not always heed Biden's advice. Obama gave the go-ahead for the 2011 raid in Pakistan that killed al Qaeda leader Osama bin Laden despite Biden's warning that it was too risky.
Biden speaks openly about his family's tragedies including the 1972 car crash that killed his first wife, Neilia, and their 13-month-old daughter, Naomi, weeks after his election to the Senate.
He almost abandoned his political career to care for his two young sons who survived the accident but stayed on, commuting by train from Delaware to Washington to avoid uprooting them.
In 2015, his son Joseph "Beau" Biden III, an Iraq war veteran who had served as Delaware's attorney general, died from brain cancer at age 46. Biden's son Hunter struggled with drug issues as an adult.
Biden himself had a health scare in 1988 when he suffered two brain aneurysms.
Biden was born in the blue-collar city of Scranton, Pennsylvania, the eldest of four siblings. His family later moved to Delaware. Biden overcame stuttering as a boy by reciting passages of poetry to a mirror.
He was practically a political novice - having served two years on a county board in Delaware - when in 1972 he became the fifth-youngest elected senator in U.S. history.
Despite years of partisan hostilities in Washington, Biden remained a believer in bipartisanship. During his time in the Senate, Biden was known for his close working relationships with some of his Republican colleagues. In addition, a number of disaffected Republicans, including former government officials and former lawmakers, alarmed at Trump's presidency have endorsed Biden.
Biden also advocated for America's role as a leader on the world stage at a time when Trump was abandoning international agreements and alienating longtime foreign allies.
One of Biden's accomplishments as a senator was helping to secure passage in 1994 of a law called the Violence Against Women Act to protect victims of domestic crimes.
While in the Senate, Biden built up a specialty in foreign affairs and at one time headed the Foreign Relations Committee. He voted in favor of authorizing the 2003 Iraq invasion before becoming a critic of Republican President George W. Bush's handling of the war.
Biden was criticized as chairman of the Senate Judiciary Committee in 1991 for his handling of sexual harassment accusations against Republican President George H.W. Bush's conservative Supreme Court nominee Clarence Thomas by former aide Anita Hill. Liberals criticized him for doing too little to defend Hill's allegations, which Thomas had denied.
The committee held explosive televised hearings prior to Thomas's eventual Senate confirmation. Thomas accused Biden's committee of conducting "a high-tech lynching for uppity Blacks who in any way deign to think for themselves, to do for themselves, to have different ideas."
In May of this year, Biden denied a former Senate aide's accusation that he had sexually assaulted her in 1993, calling the claim "not true" and saying "unequivocally it never, never happened." The allegation was made by a California woman named Tara Reade who worked as a staff assistant in Biden's Senate office for about 10 months.
Reade was one of eight women who in 2019 came forward to say Biden had hugged, kissed or touched them in ways that made them uncomfortable, though none accused him of sexual assault. Reade publicly accused him of the assault months later.