Joe Biden said Thursday he asked former President Barack Obama not to endorse his presidential campaign, saying whoever won the Democratic nomination should do so 'on their own merits.'

'I asked President Obama not to endorse. Whoever wins the nomination should win it on their own merits,' the former vice president told reporters in the Wilmington, Delaware, Amtrak train station.

Obama released a statement Thursday that praised Biden but stopped short of endorsing his presidential bid, raising questions about how much the former president would be willing to do to help his former running mate win the Democratic nomination.

Former Vice President Joe Biden said he asked former President Obama not to endorse his campaign

Biden was spotted hugging a cop

Biden stopped at Gianni's pizza in Wilmington

Biden also declined to answer a question on why he's the best choice for Democrats in 2020, saying: 'That will be for the Democrats to decide.'

He had a brief exchange with reporters in the Amtrak station in Wilmington, Delaware, that bears his name: The Joseph R. Biden Jr. Railroad Station.

He was also spotted hugging a cop in the station and he stopped by his favorite pizza place - Gianni's pizza - for lunch.

Biden was casually dressed in a blue-button down shirt and made small talk with people in the pizza parlor.

'America is coming back to like we used to be, ethical, straight, telling the truth, supporting our allies, all those good things,' he told reporters outside the restaurant.

The first images - in his home town where he's very popular - show the former vice president glad handling, posing for pictures and being a regular Joe. He called people by name and asked about their families as he left the pizza place. He got a pizza and soda to go, signature aviator sunglasses on as he departed.

The former vice president ended months of speculation Thursday when he formally entered the race for the Democratic presidential nomination in an announcement that struck directly at President Donald Trump and laid out the former vice president's vision to led the nation.

'We are in the battle for the soul of this nation,' Biden declared in his announcement video. 'The core values are standing in the world. Everything that has made America America is at stake. That's why today I'm announcing my candidacy for president of the United States.'

Joe Biden greets people during a stop at Gianni's Pizza in Wilmington, Del.

Former Vice President Joe Biden formally announced his presidential bid in a video

Trump wasted no time hitting back and dubbed Biden with the moniker 'Sleepy Joe,' mocking him with a nickname as he has done with other political rivals in the past.

'Welcome to the race Sleepy Joe. I only hope you have the intelligence, long in doubt, to wage a successful primary campaign. It will be nasty - you will be dealing with people who truly have some very sick & demented ideas. But if you make it, I will see you at the Starting Gate!,' Trump wrote on Twitter Thursday morning.

Biden, 76, will share the primary field with at least 20 other candidates, a record for a major U.S. political party.

His entry comes as new poll shows he would defeat President Trump if the general election were held today.

Biden struck hard and direct at Trump in his three-and-a-half minute announcement video.

'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.

The former vice president cited the white supremacist march through Charlottesville, Va., in 2017, and President Trump's response to it as the reason behind his decision to make a third bid for the White House.

'I knew the threat to this nation was unlike any I had seen in my lifetime,' he noted.

He particularly pointed to Trump's line that there are 'very fine people on both sides.'

'Some very fine people on both sides, very fine people on both sides? With those words, the president of the United States assigned a moral equivalency between those spreading hate and those with the courage to stand against it. And in that moment I knew the threat to this nation was unlike any I had ever seen in my lifetime,' Biden said.

Democrat Joe Biden leads President Donald Trump by eight points in a hypothetical 2020 matchup, according to a new poll

The poll of 1,992 registered voters was conducted between April 19 and 21

Trump, notably, has not struck out at Biden for being a socialist or liberal.

The former vice president has a long, strong legislative record as a moderate but he will face more progressive rivals in the battle for the nomination.

And that is the internecine battle Democrats are facing among themselves: the more moderate, blue-collar voters (who swung to Trump in 2016 and put him in the White House) versus the younger, more progressive and diverse generation.

Biden Campaign Staff Greg Schultz, Campaign Manager Kate Bedingfield, Deputy Campaign Manager and Communications Director Pete Kavanaugh, Deputy Campaign Manager Anthony Bernal, Deputy Campaign Manager and Chief of Staff to Dr. Jill Biden Symone Sanders, Senior Advisor Cristobal Alex, Senior Advisor Brandon English, Senior Advisor Daniel McCarthy, Chief Operations Officer and Chief Financial Officer Dana Remus, General Counsel Erin Wilson, National Political Director Vanessa Cardenas, National Coalitions Director Michelle Kwan, Surrogates Director Kurt Bagley, National Organizing Director Katie Petrelius, National Finance Director PJ Alampi, Director of Digital Content Becca Siegel, Chief Analytics Officer Ashley Williams, Trip Director Kate Berner, Deputy Communications Director for Messaging Meghan Hays, Deputy Communications Director for Strategic Planning Bill Russo, Deputy Communications Director for Press Jamal Brown, National Press Secretary TJ Ducklo, National Press Secretary Remi Yamamoto, Traveling National Press Secretary Sherice Perry, Communications Director for Dr. Jill Biden Andrew Bates, Director of Rapid Response Kamau Marshall, Director of Strategic Communications Advertisement

The president labeled those liberal left candidates as people with 'some very sick & demented ideas,' in his tweet Thursday.

A prominent liberal group has already disavowed the former vice president.

Justice Democrats, the group that helped progressives like Rep. Alexandria Ocasio-Cortez take office, slammed Biden in a statement Thursday.

'The old guard of the Democratic Party failed to stop Trump, and they can’t be counted on to lead the fight against his divide-and-conquer politics today. The party needs new leadership with a bold vision capable of energizing voters in the Democratic base who stayed home in 2016,' the group said.

Biden's entry into the race Thursday follows a shock poll released on Wednesday, which put him eight points ahead of Trump and had the 76-year-old leading a packed Democrat primary field.

The Morning Consult/Politico poll shows Biden leading Trump 42 per cent to 34 per cent in a general election matchup.

The poll of 1,992 registered voters was conducted between April 19 and 21.

It showed Biden with a strong lead over Trump among women, whom he led by 17 points, millennials with a 22-point lead and independents, up 10 points.

The former vice president also announced his campaign staff on Thursday including campaign manager Greg Schultz, who ran Biden's PAC American Possibilities and served as his political director in the White House; Symone Sanders, a prominent African American political strategist who served as Bernie Sanders press secretary for his 2016 campaign, as a senior adviser; and Michelle Kwan, a two-Olympic medal winning figure skater, as his surrogates director.

Biden's announcement video also touched on issues important to Democrats - striking at the moral character of President Trump while highlighting the racial issues that have caused concern.

'I don't see how you could do anything that goes more directly at some of the constituencies of the Democratic Party than putting Charlottesville front and center,' former Obama campaign manager David Axelrod said on CNN Thursday.

The former vice president enters the race as the pejorative front runner.

Even before he pulled the trigger on his campaign, his strong national name recognition has made him the odds-on favorite to square off against President Trump next year.

Vermont Sen. Bernie Sanders, the only declared candidate who is older than Biden, is running in second place with 23 per cent average backing. No other potential Democratic nominee is polling in double digits.

Biden's task will be to grow his natural base faster than his competitors can catch up to him and to dispel the party's fear that a series of sexual harassment allegations have saddled him with a ceiling that no amount of joshing and grinning can break through.

Biden, seen here with wife Jill at the 2013 inaugural ball, will appear with her on ABC's 'Good Morning America' next week

Former President Barack Obama praised Biden in a statement Thursday but did not formally endorse his presidential bid

Biden waves to the crowd after he stopped for pizza on Thursday

He will position himself as a level headed statesman and highlight his roots as a blue-collar man from Scranton, Pennsylvania, who never lost touch with his hardscrabble beginnings.

It's those middle class roots and appeal to Midwest voters in Pennsylvania, Wisconsin, Ohio and Michigan that are said to worry Republicans as those are the states that helped put Trump in the White House.

Pennsylvania is getting a heavy focus from Biden from the start. He'll hold rally with Teamsters in Pittsburgh on Monday and then, on May 18, he'll hold a rally in Philadelphia.

Trump won the state in 2018, the first time in over 20 years a Republican captured it, helping hand him the Oval Office.

Biden's first high-profile endorsements on Thursday came from Democratic U.S. senators who hail from his native Pennsylvania and his childhood state of Delaware.

Chris Coons, who holds the Delaware seat Biden once occupied, called the former vice president 'better prepared than anyone to lead America on the world stage at a time when our commitments to our allies and our values are being questioned like never before.'

'Joe knows what it means to strengthen our alliances, stare down our adversaries, and represent the best of America abroad,' Coons said in a statement.

Biden Campaign Schedule April 26: Appears on ABC's 'The View' April 29: Speech to union members in Pittsburgh, Pennsylvania April 30: Biden and Jill Biden appear on ABC's 'Good Morning America' May 18: Rally in Philadelphia Advertisement

Sen. Bob Casey of Pennsylvania said America is at a 'make-or-break moment for the middle class, our children and our workers,' and that 'America needs Vice President Joe Biden to be its next President.'

Former President Barack Obama did not leap up to support his two-time running-mate.

A person familiar with Obama's thinking said Thursday that the 44th president is 'excited by the extraordinary and diverse talent exhibited in the growing lineup of Democratic primary candidates.'

But 'it's unlikely that he will throw his support behind a specific candidate this early in the primary process — preferring instead to let the candidates make their cases directly to the voters,' the source said.

In public, Obama spokeswoman Katie Hill told reporters: 'President Obama has long said that selecting Joe Biden as his running mate in 2008 was one of the best decisions he ever made.'

'He relied on the Vice President's knowledge, insight, and judgment throughout both campaigns and the entire presidency,' said Hill. 'The two forged a special bond over the last 10 years and remain close today.'

The former Vice President said in the video: 'We are in the battle for the soul of this nation'

Biden talks with officials after speaking at a rally in support of striking Stop & Shop workers in Boston on April 18

The Republican National Committee leaped to mock Biden for failing to lock his former boss into a Day One endorsement.

'Joe Biden has been running for president and losing since the ‘80s. 2020 won’t be any different. Biden’s fingerprints are all over foreign policy blunders and the weakest economic recovery since World War II,' said RNC Communications Director Michael Ahrens.

'We don't need eight more years of Biden. Just ask President Obama, who isn't even endorsing his right-hand man.'

And RNC Chairwoman Ronna McDaniel tweeted Thursday morning: 'If Joe Biden wants to keep score: In 8 years, Biden & Obama had a net loss of 193,000 manufacturing jobs. In just over 2 years, @realDonaldTrump has created 453,000 manufacturing jobs. Don’t let Biden take us backwards!'

Meanwhile, Biden's team worries about his fundraising ability and his tendency to commit gaffes.

Money is said to be one of the campaign's biggest worries.

Although Biden has long standing ties to the party's elders and a long list of wealthy supporters he can call at a moment's notice, he'll face questions if he can harness the social media and small donor power that Beto O'Rourke and Bernie Sanders have used to fuel their candidacy.

Highlighting his campaign's concern about cash, his first post-presidential stop will be a fundraiser.

On Thursday, a group of Philadelphia-based Democratic insiders with ties to Obama and Hillary Clinton are planning a fundraiser at the home of David L. Cohen, executive senior vice president of Comcast. The former vice president will attend, the Philadelphia Inquirer reported, and is aiming to raise $500,000 at the event.

On Friday, Biden will appear on ABC's 'The View,' followed by a rally in Pittsburgh on Monday. He and wife Jill will sit down with ABC's Robin Roberts for Tuesday's 'Good Morning America.'

Sandwiched in between and throughout the next few weeks will be visits to the early voting states in the Democratic primary process.

Four years Trump's senior, Biden would be the oldest person ever elected president should he win.

He is expected to campaign as an 'Obama-Biden Democrat,' who is as pragmatic as he is progressive, in a move to appeal to those nostalgic for the former president.

He'll also have to balance the working-class voters who are his strength with the younger, more diverse crowd who came out for Obama in historic numbers but stayed home for Hillary Clinton.

Biden speaks at the IBEW Construction and Maintenance Conference in Washington earlier this month

Former Vice President Joe Biden speaks at the Biden Courage Awards in New York last month

With a public record that stretches back a half a century, Biden's challenges are easy to find.

First and foremost were the recent allegations stemmed from years of Biden's hugs and kisses to women, some of whom said the touching was inappropriate and unwelcome.

Biden is known for demonstrating affection in public. It was often the subject of jokes while others labeled him 'Creepy Uncle Joe.'

The recent scandal, however, found the former vice president staring down a wave of allegations from women, whose fury against Trump's election and leadership in the #MeToo movement have made them a force in the 2020 contest.

It's also left the Democratic Party in the awkward position of watching one of its favorite sons try to calm a storm that has engulfed other politicians.

Biden, trying to stem the tide ahead of his expected announcement, broke his silence on the scandal in early April, saying he 'tried to make a human connection' with his actions but 'will be more mindful and respectful of people's personal space' in the future.

'I always try to be in my career, always tried to make a human connection. That's my responsibility, I think. I shake hands, I hug people. I grab men and women by the shoulders and say you can do this, whether they're women, men, young, old. It's the way I've always been and tried to show that I care about them and I'm listening,' he said in a video posted to his Twitter account.

The scandal began when former Nevada politician Lucy Flores accused him of making her uncomfortable during a 2014 campaign appearance when he kissed the back of her head.

Since she spoke, three additional women have come forward.

But other women defended the former vice president, saying they found comfort in his hugs.

The scandal will likely be one of the first items he'll have to address in his upcoming set of interviews on ABC.

Biden's first White House bid in 1988 ended after a plagiarism scandal.

In 2008, he dropped out after less than 1 per cent of the vote in the Iowa caucuses, a fact Trump has mocked him for.

'He ran two or three times, he never got about one percent. And then [Barack] Obama came along and took him off the trash heap, and he became a vice president, and now he's leading,' Trump told Fox News in January.

Later in 2008, Obama named Biden his running mate, in part to use Biden's elder statesman experience to balance out his lack of time on the national political scene.

Additionally, Biden's willingness to work with Republicans has caused him political headaches.

He was forced to walk back a comment last month that Vice President Mike Pence is 'a decent guy' after intense blowback from liberal activists upset with Pence's opposition to gay rights.

Biden was also a close friend of the late Sen. John McCain and spoke at one of of his memorial services.

Biden's first accuser, former Nevada politician Lucy Flores, said she was 'mortified' when Biden planted a 'big, slow kiss' on the back of her head as she waited to take the stage at a campaign rally five years ago

Biden speaks at a rally in support of striking Stop & Shop workers in Boston last week

First elected to the Senate in 1972, Biden has a long record in Congress that he will have to defend.

The most prominent has been the 1991 confirmation hearing for Supreme Court nominee Clarance Thomas. As chairman of the Senate Judiciary Committee, Biden allowed Anita Hill, who had accused Thomas of sexual harassment, to face harsh questions form an all-male panel. Thomas was later confirmed to the court.

Biden has since apologized for his role in the hearing.

His deputy campaign manager Kate Bedingfield said on CNN Thursday that Biden and Hill have spoken but she declined to give any details on the timing or nature of the conversation.

'I'm not going to get into their private discussions, but they have spoken,' Bedingfield said.

But in the #MeToo era, particularly after the contentious confirmation of Supreme Court Justice Brett Kavanaugh, his apology may not be enough to silence the issue.

The former vice president also has a compelling personal story to back up his professional experience.

A a son of Scranton, Pa., his wife Neilia and daughter Naomi were killed in a car crash in December 1972, shortly after he was first elected to the Senate.

Sons Beau and Hunter survived. Biden went on to marry Jill Jacobs in 1977 and have another daughter.

But Beau died in May 2015 of brain cancer. Biden opted not to run in 2016, in part because of Beau's death, despite his dying son asking him go for it.

Biden reflected on that in a book he wrote about his conversations with Beau.

'He was worried that what I'd worked on my whole life, the things that mattered to me the most since I was a kid, that I'd walk away,' Biden said.