WASHINGTON — After months of speculation, former Vice President Joe Biden is officially in the 2020 race for president, making the announcement Thursday.

He is a top contender, with polls ranking him above the other Democratic candidates.

For the past few months, even without a platform, Biden has still been Democrats' top choice for their presidential nomination.

The former vice president joins the field with a political career that spans decades.

Elected to Congress back in 1972, he is the longest-serving senator in Delaware history.

He has already run for president twice, both times withdrawing. The first time was in 1988, when he faced allegations of plagiarism. The second time was in 2008, when he eventually signed on as presidential candidate Barack Obama’s running mate.

Biden touts his blue-collar Scranton, Pennsylvania, roots and embodies a folksy style that has caused a few gaffes in his career. That includes a 2010 incident in which he used the words "It's a f**cking big deal" when he was describing a health care bill signing and didn't realize the microphone was on.

Behind that toothy smile has also been heartbreak.

Just six weeks after his 1972 election victory, Biden's wife and daughter were killed in a car crash, landing his two boys in the hospital.

And in 2015, Biden's eldest son, Beau, died of brain cancer, which drove the vice president's decision not to run in 2016.

"I miss him every day. He was my soul," Biden said.

Since leaving office, Biden continues to be a strong voice in the party.

In January 2017, Obama surprised Biden with the nation's highest civilian honor, the Presidential Medal of Freedom.

Biden's 2020 campaign launch comes amid several women accusing him of making them deeply uncomfortable, invading their personal space.

No one has formally accused Biden of sexual misconduct.

In response, Biden has said: "I'll be much more mindful, that's my responsibility, my responsibility and I'll meet it."

His decision to run in 2020 was made in part by a wish from his late son, who wished for Biden to become the next president.

"You know, we're focusing on the inspiration of Beau rather than the loss of Beau," he said.