As the former vice-president enters a crowded 2020 field, will his well-documented past of confusing and embarrassing moments work against him?

After months of speculation and hinting, Joe Biden has officially announced his candidacy for the Democratic nomination for the presidency in the 2020 US election.

Biden, the 76-year-old former vice-president and senator from Delaware enters a crowded field of competitors, but polls in recent weeks have consistently shown him leading the pack, perhaps because of his experience and lengthy record in office.

But unlike some of his much younger opponents, it’s his decades in the public eye, and in particular his well-documented history of confusing or downright embarrassing gaffes and misstatements, that may end up working against him.

He even made a gaffe about his intentions to run for the White House. Just last month he seemed to accidentally let it slip that he was running, saying at a dinner for the Delaware Democratic party that he has “the most progressive record of anybody running”. After cheers from the crowd Biden seemed to recognize the mistake, and jokingly gave the sign of the cross, saying he “didn’t mean it”.

Here are some other memorable moments:

Biden ‘being Biden’

Biden’s awkward behavior over the years is not limited to what he has said, but also how he acts. Several women have recently come forward to say he has made inappropriate physical contact with them, leaving them feel uncomfortable.

Facebook Twitter Pinterest Joe Biden puts his hands on Stephanie Carter’s shoulders as her husband, Ashton Carter, is being sworn in as secretary of defense on 17 February 2015. Photograph: Alex Wong/Getty Images

Infamously in 2015, while Ashton Carter was being sworn in as the secretary of defense, Biden put his hands on his wife Stephanie’s shoulders, rubbing them and appearing to whisper in her ear. “Joe Biden, We Need to Talk About the Way You Touch Women,” Gawker wrote at the time, collecting a series of photo ops in which Biden appears to behave in an overly familiar way with women, young and old alike. “America Shouldn’t Tolerate ‘Biden Being Biden,’” Time remarked.

Stephanie Carter wrote a blogpost published on Medium on 31 March defending Biden, saying it had merely been a “moment between close friends”.

The living and the dead

In 2010, at a St Patrick’s Day reception for Brian Cowen, Biden got confused over which of the then Irish prime minister’s parents had passed away.

“His mom lived in Long Island for 10 years or so, God rest her soul,” he said, before catching his mistake. “Although she’s, wait. Your mom’s still alive. It was your dad that passed. God bless her soul. I gotta get this straight,” Biden said to a big laugh from the crowd, showing that even when he screws up, his supporters often find it charming.

Stand up for America

At a campaign stop in Missouri in 2008, then vice-presidential nominee Biden exhorted state senator Chuck Graham to stand up for a round of applause. Graham is a paraplegic after a car accident he had at age 16.

“Stand up, Chuck, let them see you,” Biden said.

“Oh, God love ya, what am I talking about,” Biden said. “I tell you what, you’re making everybody else stand up though, pal,” he said. He added: “You can tell I’m new.”

Fresh ideas

Facebook Twitter Pinterest Barack Obama and Joe Biden at the US Conference of Mayors in Washington DC on 21 January 2010. Photograph: Rex Features

In the midst of his campaign for the Democratic nomination for president in 2007, Biden took broad swipes at his opponents Hillary Clinton, John Edwards and Barack Obama, including one that was downright puzzling about the future president.

“I mean, you got the first mainstream African American who is articulate and bright and clean and a nice-looking guy,” he said. “I mean, that’s a storybook, man.”

“Joe Biden: moron racist, or poorly transcribed?” the Economist asked.

Biden swiftly attempted to clarify his intent, saying he should have used the word “fresh” instead of “clean” on The Daily Show with Jon Stewart.

“What I meant was that he’s got new ideas, he’s a new guy on the block,” he said, while Stewart looked on skeptically. “It’s not working, right?” he joked to laughter from the audience.

In his own words

The 2008 election wasn’t the first time Biden ran for president. After it was revealed that Biden had taken to adopting language used by then British Labour party leader Neil Kinnock – not only turns of phrases but taking parts of his biography as his own on stump speeches – Biden dropped out of the 1988 race.

Clips of the speeches were put together by challengers, damaging Biden’s reputation.

Biden initially called it a “tempest in a teapot” at the time, but after further accusations of plagiarism were reported, stretching back to his days in law school, he stepped down.

Crazy ‘Uncle Joe’

As troubling as some of his misstatements might be, and as serious some of the concerns people have about Biden’s retrograde positioning among a new crop of progressive candidates, a sizable percentage of the US electorate finds the often goofy Biden charming.

It didn’t hurt matters that Obama often reacted to them with bemusement. “I don’t remember exactly what Joe was referring to, not surprisingly,” Obama quipped after a typically confusing statement from Biden about the passage of a stimulus package in 2010.

Gaffe machine

Facebook Twitter Pinterest Joe Biden and Lisa Murkowski at the US Capitol in Washington DC on 5 January 2011. Photograph: Jonathan Ernst/Reuters

In 2015, presidential candidate Donald Trump spoke about the prospect of squaring off against Biden if he had ended up running.

“I think I’d match up great,” he said. “I’m a job producer. I’ve had a great record, I haven’t been involved in plagiarism.”

We may yet get to see how that works on the 2020 campaign trail. Trump is not exactly gaffe-free, to put it mildly.

“I hope it’s Biden,” Trump said again last month. “When I say something that you might think is a gaffe, it’s on purpose. It’s not a gaffe. When Biden says something dumb, it’s because he’s dumb.”

“I am a gaffe machine,” Biden admitted in December when asked about potential liabilities of his campaign. “But my God what a wonderful thing compared to a guy who can’t tell the truth,” he said.

• This article was amended on 25 April 2019. Joe Biden dropped out of the presidential race in 1988, not 1998 as previously stated.