Three of the nine Democratic presidential candidates tried to differentiate themselves from President Bush and each other Thursday in a forum for mayors from across the country.

Appearing before the National Conference of Black Mayors (search), Rep. Dick Gephardt focused on a health care proposal he announced Wednesday that would cost an estimated $692 billion from 2005 through 2007.

He said all of Bush's tax cut passed two years ago and any other his administration signs into law would be repealed to pay for the plan, intended to provide health care to most of the 41 million uninsured Americans.

"No American should live in terror because they don't have health insurance," Gephardt (search) said.

Former Vermont Gov. Howard Dean (search), a physician, also has called for repeal of the tax cuts to cover health care but says his plan would cost half as much as Gephardt's.

He said Bush has foisted unfunded homeland security requirements on cities, "but he wants a $670 billion tax cut for Ken Lay and the boys just down the street," referring to the former leader of Houston-based Enron Corp.

Dean said his health care plan would guarantee insurance for all Americans under 25, add prescription benefits to Medicare and help small businesses and self-employed workers cover health care costs.

"You can do this for half the president's tax cut," Dean said. "It's not a Cadillac. Everyone has to pay something. But it'll work."

Sharpton (search) addressed doubts about his candidacy, noting only one candidate will win the nomination, leaving losers with plenty of company.

The other six candidates seeking the 2004 Democratic nomination are Sen. John Kerry of Massachusetts (search), Sen. Joe Lieberman of Connecticut (search), Sen. Bob Graham of Florida (search), former Illinois Sen. Carol Moseley Braun (search) and Rep. Dennis Kucinich of Ohio (search).