Former vice presidential nominee and Sen. John Edwards (D-N.C.) scored the biggest hit of the day when he challenged his competitors to stop accepting contributions from lobbyists. Sen. Barack Obama (D-Ill.) does not accept donations from lobbyists, which Edwards acknowledged.

“In 35 years of public service, nobody seriously thinks I could be influenced by a lobbyist,” Clinton said, defending her decision to continue to accept contributions.

“Lobbyists represent real interests, nurses, social workers…somehow the idea that a contribution is going to influence my record,” is not rooted in reality, Clinton added.

Sen. Chris Dodd (D-Conn.) said he favored a publicly financed campaign system, and Rep. Dennis Kucinich (D-Ohio) challenged Edwards to stop taking money from managers of hedge funds.

Clinton’s campaign defended her statement by noting that lobbyists help Obama and Edwards raise money, and that lobbyists from Illinois give to Obama.

“That apparently is a distinction that's important to him,” said Phil Singer, a Clinton spokesman. “Every campaign makes its own choices here.”

The forum included three 30-minute segments on domestic policy, foreign affairs, and philosophy and sounded as political and scripted as the previous debates. Moderator Matt Bai of the New York Times began by asking Obama whether he would “tolerate” budget deficits to increase spending on health care, infrastructure, and other priorities.

After listing ways in which he would reduce spending and raise revenue, Obama said he would not short change long-term investments for short-term budget reduction.

Appearing together on stage in a ballroom at the McCormick Place Convention Center, where the 1968 Democratic Convention and the anti-war riots were held, the candidates’ appearance had all the trappings of a debate, although the candidates did not engage each other until the very end.

Only former Sen. Mike Gravel (D-Alaska), as he has done in previous debates, criticized his fellow Democrats.

During the last part of the debate, candidates were asked if they would visit all 50 states and hire a White House blogger if elected president. Edwards said his wife, Elizabeth, who blogs on DailyKos, would be his blogger.

Gravel told the audience to “do it yourself.”

With Alaska’s three-member congressional delegation under federal investigation, a moderator jokingly asked Gravel whether all politicians in Alaska were corrupt.

“It’s a source of great embarrassment for the state, but look all pols walk in the mud because of the way the system is structured,” Gravel said.

The mood was rather light as the audience and candidates sang “Happy Birthday” to Obama, who turned 46. Sitting in an arc in front of a dark blue curtain, Edwards, Dodd and Kucinich wore white shirts and blue ties; Obama and Richardson donned white shirts and red ties; Gravel dressed informally: khaki pants and a blue oxford shirt.

There were no slips or gaffes except by one of the moderators who mistakenly called Sen. Clinton, “President Clinton.”

The candidates will return to Chicago on Tuesday for a debate sponsored by the AFL-CIO, which will be moderated by MSNBC’s Keith Olbermann on Tuesday outdoors at Soldier Field.

YearlyKos officials went to great lengths to defend Clinton from criticism for initially planning to skip the post-forum gatherings, saying the New York senator was not snubbing them. Instead of talking one-on-one with the liberal bloggers and activists after the event, Clinton decided to hold the ‘breakout session’ before the start of the forum.

Clinton heads to fundraisers in the Hamptons.

Obama met with a group of bloggers before the event started.