Former Vice President Joe Biden is running for president in 2020

• Former Vice President Joe Biden announced he's running for president in 2020.
• Polls have shown Biden has good shot of defeating Trump, but he's also poised to face stiff competition among a wide field of Democrats.
• This is not the first time Biden has sought the highest office in the land. He ran a failed campaign for president in 1988 while serving as a senator from Delaware, and another in 2008 before he was tapped as Obama's running mate.

Former Vice President Joe Biden on Thursday announced he's running for president in 2020.

Biden, known affectionately by his supporters as "Uncle Joe," remains popular nationwide and has been pegged as a leading contender for the Democratic nomination for president.

He announced his candidacy in a video published early Thursday morning.

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Biden's entrance into the race comes after more than a dozen Democrats have announced 2020 presidential runs. By joining the race, Biden contributes a significant amount of experience to a field of young and diverse candidates.

In the days leading up to his announcement, Biden's top aide Greg Schultz huddled with chiefs of staff for Democratic lawmakers on Capitol Hill to shore up support for the campaign. Schultz also questioned staffers on which issues were important in various congressional districts.

The former vice president has also been the subject of several accusations that he inappropriately touched women and invaded their personal space.

Biden has pledged to be more mindful of how he interacts with individuals and respects changes in what he characterized as "social norms," but has also repeatedly cracked jokes about being allowed to touch people during public events.

And several high-profile Democrats have already shown eagerness to back Biden in 2020, including veteran Sen. Dianne Feinstein of California, who touted Biden as her top choice.

"I watched him as vice president. I've seen him operate," she said. "I've seen him perform and I think he brings a level of experience and seniority, which I think is really important."

Weeks before Biden's announcement, Delaware Sen. Chris Coons advocated for Biden in an interview with CBS, contrasting his message with President Donald Trump's.

"From my perspective, the worst thing about President Trump is that he sees divisions in our country and he cracks them open. He exploits them for his own personal and partisan advantage," Coons said. "Joe Biden is someone who sees the differences in our country and inspires us, reminds us of the ways in which we've overcome them in the past and will lift us up."

But at 76-years-old, his age is a liability and some feel the former vice president is too old to be running.

His connection to former President Barack Obama will be a boon among Democratic voters but could present complications should Biden win the nomination. Obama remains an extremely popular figure, but President Donald Trump will likely use the Obama administration's policies as a point of attack against Biden whenever he can.

Biden has made no secret of his disdain for Trump, and will undoubtedly lambaste the president routinely as he campaigns.

Read more: Joe Biden's long history in public life could come back to haunt him if he decides to run for president

Biden's long political career leaves him open to criticism on an array of issues, such as his aggressive questioning of Anita Hill during the confirmation hearings of Supreme Court Justice Clarence Thomas, and his well-documented tendency for embarrassing gaffes.

But the former vice president has pointed to his breadth of experience as one of his greatest strengths. At an event on his book tour in early December, Biden described himself as the "most qualified person in the country to be president."

"The issues that we face as a country today are the issues that have been in my wheelhouse, that I've worked on my whole life," he said.

Polls have shown Biden has good shot of defeating Trump, but he's also poised to face stiff competition among a wide field of Democrats.

This is not the first time Biden has sought the highest office in the land. He ran a failed campaign for president in 1988 as a senator from Delaware, and another in 2008 before he was tapped as Obama's running mate.