WILMINGTON, Del. – Joe Biden is officially in the race for president.

His long-awaited answer to one of the biggest political questions in the country the past few months ended Thursday, and it makes him one of 20 Democrats vying to become the party's 2020 presidential nominee.

"The core values of this nation, our standing in the world, our very democracy, everything that has made America America is at stake," he said in a video posted to Facebook and Twitter on Thursday morning. "That's why today I'm announcing my candidacy for president of the United States."

The announcement from the 76-year-old former vice president comes three years after he declined to seek the country's highest political office – a time when he and his family were grieving the death of his oldest son, former Delaware Attorney General Beau Biden.

In his announcement, Biden went after President Donald Trump and the statements he made after violent clashes between activists and white supremacists in Charlottesville, Virginia, in 2017.

In the wake of the demonstrations, which killed one person, Trump said there were fine people on "both sides," a remark that drew wide condemnation.

"With those words, the president of the United States assigned a moral equivalence to those spreading hate and those with the courage to stand against it," Biden said in the video. "In that moment, I knew the threat to this nation was unlike any I had ever seen in my lifetime."

The former vice president continued, speaking directly into the camera.

"We are in the battle for the soul of this nation," he said. "I believe history will look back on four years of this president and all he embraces as an aberrant moment in time.

"But if we give Donald Trump eight years in the White House, he will forever and fundamentally alter the character of this nation, who we are, and I cannot stand by and watch that happen," he said.

Thanks to the name recognition that comes with holding national office, Biden has been among the front-runners in Democratic polling for months, even as he waited along the sidelines.

Yet, in recent weeks, controversy struck after four women claimed Biden had hugged, kissed or rubbed noses with them without permission.

In the wake of the allegations, Biden's lead in some recent primary state polls weakened as support for U.S. Sen. Bernie Sanders and South Bend, Indiana, Mayor Pete Buttigieg has grown.

The Democratic field of candidates includes a former Cabinet secretary to President Barack Obama, sitting senators, current and former U.S. representatives and a former governor.

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Several candidates have pulled their party to the left, calling for "Medicare for all" and tighter regulations on fossil fuels. It remains unclear whether a similar a progressive tilt will come from the Biden camp in the months before the first state primaries early next year.

Biden embraced the "middle class Joe" moniker while he was vice president, yet before that he represented the moderate, pro-business state of Delaware for 36 years in the U.S. Senate.

There, he championed the Violence Against Women Act and numerous bills designed to combat drug use, including legislation that imposed stiffer prison sentences for the possession of crack cocaine than those for powder cocaine.

Jeffrey A. Sonnenfeld, president of the Chief Executive Leadership Institute, says Biden today has a built in base in the political center as many socially liberal and economically conservative business leaders are excited about his candidacy.

Businesses are craving an experienced politician who can avert the economic uncertainty that has surrounded the Trump administration, he says.

They will support Biden, a lifelong Democrat, even though he may not favor all of their preferred, "parochial" tax cuts, says Sonnenfeld, who also is a professor of management at Yale University.

"The runaway biggest fear they (businesses) have is the political instability in Washington," he says. "Joe Biden they see as a breath of fresh air."

With his candidacy officially launched, many political commentators now will keep watch on his political donations, particularly during the first week.

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Jim Chanos, an investment manager and major Democratic donor, told CNBC in February that he would throw his support and influence behind a Biden presidential run.

But while Biden may reap support from well-heeled moderates if he embraces the party's center, that could also make him a target of political barbs from progressives.

Biden's candidacy could become a measure of whether Democratic voters have shifted as far to the left as some of his fellow presidential candidates.