President Obama will deliver the eulogy around noon. You can watch in the player above. FOX 2 app users, click here.
The former Delaware attorney general died last Saturday of brain cancer. He was 46.
An overflow crowd of 1,000 gathered for the funeral at St. Anthony of Padua Roman Catholic Church, where Obama was to deliver a eulogy. Leading political figures also were there, including the U.S. Senate majority and minority leaders, Attorney General Loretta Lynch and her predecessor, Eric Holder, and other Cabinet officials.
Also paying their respects were mourners from across Delaware and beyond, who lined up hours in advance, drawn by their strong bonds to the Biden family.
"Joe Biden is Delaware, and his son is also Delaware to me," said Lisa Rial, 54, who grew up in Delaware but lives in Pennsylvania. "They're synonymous with Delaware."
In addition to Obama, Biden's two surviving children, Hunter and Ashley, were to speak, as was Gen. Ray Odierno, the former top U.S. commander in Iraq, where Beau Biden once served. Coldplay lead singer Chris Martin was to perform a solo. The White House said Martin had heard through a family friend that Beau Biden was a Coldplay fan and volunteered to attend.
Beau Biden's casket lay in honor in the state Senate chamber on Thursday ahead of a public viewing at St. Anthony on Friday.
The vice president, whose wife and baby daughter were killed in a car crash four decades ago, developed a reputation over the years for possessing a deep ability to comfort those in grief. Often, he is called upon to eulogize fellow American leaders.
In 2012, he spoke of his son's service in Iraq as he tried to comfort a group of grieving military families.
"When he came home - it's going to sound strange to you - we felt almost a little guilty because he came home," Biden said at that time. "Because there's so many funerals I've attended, so many bases I've visited. And you know, not all losses are equal. Not all losses are equal."
Beau Biden, who died a week ago, served two terms as attorney general before setting his sights on the governor's mansion. Many imagined his career would mirror that of his father, who represented Delaware for decades in the U.S. Senate before becoming vice president.
But in 2010, at age 41, Beau Biden suffered a stroke. He was diagnosed with brain cancer three years later. He returned to work after what doctors said was a successful operation to remove a small lesion, but his illness returned, and he died last Saturday, less than two weeks after being admitted to Walter Reed National Military Medical Center in Bethesda, Maryland.
His death drew passionate expressions of sympathy from across the political spectrum, the sense of sadness heightened by the tragedy that the Biden family has endured over the years. It was just weeks after Joe Biden was first elected to the Senate in 1972 that Beau, then age 3, and his 2-year-old brother, Hunter, were injured in the car crash that killed their mother and infant sister.
White House officials said the choice of Obama to deliver a eulogy reflected the tight personal relationship that Joe Biden and the president have developed after more than six years together in the White House.
In Washington, the House and Senate have adopted resolutions expressing sorrow over Beau Biden's death. The Beau Biden Foundation for the Protection of Children, established last week to continue his efforts to protect children from sexual predators, has already received more than 1,100 donations totaling roughly $175,000.
Associated Press writer Randall Chase contributed to this report.
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