PHILADELPHIA (CBS/AP) — After announcing Thursday in a video that he’s running for president, Joe Biden will be holding a campaign kickoff rally in Philadelphia next month. The Biden campaign announced the rally will take place on Saturday, May 18.

“Join the entire Biden family and supporters from every corner of the country in Philadelphia, PA, as we officially launch our campaign for President!” the event reads.

Biden, who is holding a fundraiser in Philadelphia on Thursday night, quickly racked up endorsements after his announcement, becoming the first Democrat running for president with the backing of more than one U.S. senator, including Sens. Bob Casey, Tom Carper and Chris Coons.

However, he didn’t receive an endorsement from former President Barack Obama, whom he served under as vice president for eight years. Biden said he asked Obama not to endorse him.

“I asked President Obama not to endorse. Whoever wins this nomination should win this on their own merits,” said Biden.

The former president, though, did weigh in on Biden’s announcement.

“President Obama has long said that selecting Joe Biden as his running mate in 2008 was one of the best decisions he ever made,” Obama spokeswoman Katie Hill said. “He relied on the vice president’s knowledge, insight, and judgment throughout both campaigns and the entire presidency. The two forged a special bond over the last 10 years and remain close today.”

Biden must compete in a field that now spans at least 20 Democrats and has been celebrated for its racial and gender diversity. As an older white man with occasionally centrist views, Biden has to prove he’s not out of step with his party. He’s yet to outline his positions on the issues defining the 2020 Democratic primary, most notably “Medicare for All,” the universal health care plan authored by Vermont Sen. Bernie Sanders that has been adopted by virtually the entire Democratic field.

Biden is paying special attention to his native Pennsylvania, a state that swung to President Donald Trump Trump in 2016 after voting for Democratic presidential candidates for decades. While Biden represented Delaware in the Senate for 36 years, he was often referred to as Pennsylvania’s third senator.

The former vice president will be in the state three times within the opening weeks of his campaign. He’ll be in Philadelphia on Thursday evening headlining a fundraiser at the home of David L. Cohen, executive senior vice president of Comcast. Biden is aiming to raise $500,000 at the event.

He will hold his first public event as a 2020 presidential candidate in Pittsburgh on Monday. Then it’s off to Iowa, home of the leadoff nominating caucuses on Tuesday and Wednesday, followed by two days in South Carolina. He’ll visit the other two early-voting states, Nevada and New Hampshire, in early May, before holding a major rally in Philadelphia.

Biden’s first media appearance is set for Friday morning on ABC’s “The View,” a move that may help him make an appeal to women whose support will be crucial to winning the primary. He also hired Symone Sanders to serve as a senior strategist, tapping a prominent African American who previously worked for Biden’s chief competitor, Bernie Sanders, in the 2016 presidential contest.

As he neared his campaign launch, Biden’s challenges have come into greater focus.

He struggled last month to respond to claims that he touched 2014 Nevada lieutenant governor nominee Lucy Flores’ shoulders and kissed the back of her head before a fall campaign event. A handful of other women have made similar claims, though none has alleged sexual misconduct.

Biden, a former U.S. senator from Delaware, pledged in an online video to be “much more mindful” of respecting personal space but joked two days later that he “had permission” to hug a male union leader before addressing the group’s national conference.

Biden also has been repeatedly forced to explain his 1991 decision, as Senate Judiciary Committee chairman, to allow Anita Hill to face difficult questions from an all-male panel about allegations of sexual harassment against Supreme Court nominee Clarence Thomas, who later was confirmed to the high court.

He has since apologized for his role in the hearing. But in the #MeToo era, particularly after the contentious confirmation of Supreme Court Justice Brett Kavanaugh, the episode remains a significant political liability.

Likewise, Biden once played a key role in anti-crime legislation that had a disproportionately negative impact on African Americans. And while several 2020 Democratic contenders have embraced the possibility of reparations to African Americans for slavery in recent weeks, Biden last month struggled to explain comments he made as a freshman senator in 1975 about the school busing debate.

His first White House bid in 1988 ended after a plagiarism scandal. He dropped out of the 2008 race after earning less than 1% of the vote in the Iowa caucuses. Later that year, Obama named Biden as his running mate.

(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)