Sen.showed up at Kennedy's home with a bottle of wine as a gift. Sen. pulled Kennedy aside to schmooze. Sen. needled Kennedy about getting older.
The shower of personal attention underscored Kennedy's star power in the White House race. The liberal senator's endorsement is among the most coveted by the eight Democratic contenders.
The birthday party was also a reminder of the tough endorsement choice Kennedy faces as the 2008 contest unfolds.
The Massachusetts senator has close ties to several candidates who are eagerly seeking his support. Whatever he decides, he's bound to disappoint some longtime friends and colleagues.
"It's going to be difficult choosing," Kennedy told The Associated Press. "I've got a lot of friends who want to be president."
Obama, Clinton and Dodd serve on the Senate Health, Education, Labor and Pensions Committee that Kennedy chairs.
"Even though they're running, they're all keeping in touch," Kennedy said. "I'm working with all of them in the Senate."
Dodd and Kennedy are longtime pals who teamed up years ago during their freewheeling bachelor days. Kennedy's sons, Ted Jr. and Rhode Island Rep. Patrick Kennedy, are backing Dodd. Kennedy's older sister Eunice gave Dodd a $5,000 check.
"He's been helpful - as I am sure he's been to others as well," said Dodd.
Former Sen.partnered with Kennedy on patients' rights legislation in 2001. New Mexico Gov. and Senate Foreign Relations Committee chairman are also Kennedy friends.
Clinton and Kennedy forged a friendship while working together on health care in the early 1990s. During the Clinton administration, Kennedy was a key White House ally. The Kennedys and Clintons often sailed together during first family vacations on Martha's Vineyard.
"Senator Clinton has a tremendous amount of respect for Senator Kennedy, and she considers him a friend," said Clinton spokesman Mo Elleithee. "We would love to earn his support in this campaign."
Kennedy's relationship with Obama does not stretch nearly as far back, but the two have struck up a friendship.
"He gave me a good bottle of wine," Kennedy joked of Obama's gift. "I'm sure it was an American wine."
Above all else, Kennedy said, he is looking for a candidate who can light a spark with voters. The policy differences between the candidates are relatively small, he said.
"Inspiration," Kennedy said. "I'm looking for a candidate able to galvanize the country to get things done. I want to find the candidate who can inspire people. That's what we need. That's what our party needs."
He said he expects the crowded field "might winnow down by mid-December. That's when people really get engaged in presidential politics."
The value of endorsements tends to get overblown in presidential politics. But Kennedy's popularity with liberal party activists who tend to dominate early voting states puts his support at a premium.
Kennedy can also lend organizational muscle by sending his Massachusetts supporters across the border to neighboring New Hampshire, the leadoff primary state. He boasts a broad national fundraising and political network as well.
"Most endorsements aren't worth much," said veteran Democratic consultant Michael Shea. "But if you get Kennedy's endorsement, it's really worth something. He wants to win."
Kennedy's support made a difference to Massachusetts colleague Sen. John Kerry's struggling 2004 primary campaign.
Kennedy gave strategic advice and key advisers to Kerry. He campaigned heavily on Kerry's behalf at a time when few believed Kerry could win. The moves helped fuel Kerry's comeback victories in Iowa and New Hampshire that paved the way to the nomination.
Kennedy, whose own presidential ambitions were dashed in 1980, said his family has kept up many of the political connections made in key states over the years.
"We've got a lot of friends out there," Kennedy said. "We've kept up the relationships."