Answering a heckler, Democratic presidential front-runner John Kerry (search) said Thursday "I never run away from anything, especially George Bush."

The Massachusetts lawmaker had just received an endorsement from Maine Gov. John Baldacci (search) when somebody from the crowd of about 400 shouted, "Why don't you tell them about your vote on the war and the Patriot Act?"

Kerry has faced criticism from some Democratic voters and rival candidate Howard Dean (search) for his vote in favor of President Bush's Iraq war resolution and his support of the Patriot Act, an anti-terrorism bill that critics say has curbed civil liberties.

"I'll explain them all as we go along," Kerry swiftly replied to the heckler. "I never run away from anything, especially George Bush."

Then he pointed to a basketball net in the Boys' and Girls' Club gymnasium and read words stenciled on the backboard. "A winner never quits and a quitter never wins," he said, calling that an apt summary of his makeup.

Just a quickly, Kerry returned to his stump speech. About 15 minutes later, he referred to the heckler and what he called the "heartfelt" opinions. Kerry noted that he protested the Vietnam War after fighting in it. He also touched on his work as a senator to shed light on the Iran-contra affair during the Reagan administration.

"I don't take a second seat to anybody in my fights for peace," he said.

Kerry did not specifically defend his vote on Iraq, but said, "There was a right way to hold Saddam Hussein accountable," including working through the United Nations and "living up to the words 'last resort."'

"Everything George Bush did was to choose the wrong way," Kerry said. He did not mention the Patriot Act.

Kerry also cast himself as a longtime enemy of special interests, despite a history of ties to lobbyists and Washington dealmaking. His chief rivals, John Edwards, Wesley Clark and Dean, are seizing on media reports about his work with special interests.

Kerry's campaign announced Thursday it has raised $5 million since Jan. 1, half of that through his Web site over a two-week period, and almost all of it -- $4.5 million -- since his Iowa victory on Jan. 19.

Campaign finance director Peter Maroney said Internet fund-raising has set campaign records nearly every day over the past two weeks.

Also Thursday, Sens. Carl Levin and Debbie Stabenow of Michigan endorsed Kerry. Both had said the results of Tuesday's primaries and caucuses would affect their decisions. Kerry won five of seven states on Tuesday.

Levin said earlier this week he was deciding between Kerry and Wesley Clark because he believes the Democratic candidate must have military experience. In a joint statement Thursday, the senators said they believed Kerry had the best chance of defeating Bush.