LOS ANGELES Democrats Barack Obama and Hillary Clinton shared a debate stage alone for the first time on Thursday, striking a cordial tone and highlighting their opportunity to make history as the next president.
"Just by looking at us, you can tell we aren't more of the same," Clinton, a New York senator who would be the first woman U.S. president, said at the final debate before Democratic nominating contests in 22 states on Tuesday. "We will change our country."
Obama, an Illinois senator who would be the first black U.S. president, said their battle for the Democratic Party's nomination in November's presidential election was a testimony to the progress of the party and country.
"We have the opportunity to make history because I think one of us two will end up being the next president of the United States of America," Obama said, sitting next to the former first lady.
The two Democratic White House contenders dropped the angry and confrontational approach of their last debate in South Carolina, directing their attacks at Republican front-runner John McCain while disagreeing on who could best lead U.S. troops out of Iraq.
"I was friends with Hillary Clinton before we started this campaign; I will be friends with Hillary Clinton after this campaign is over," said Obama, who held Clinton's chair as she sat down to begin the debate. They whispered in each other's ears in a near-hug when it was over.
The pair split the first four significant nominating contests, with Obama, 46, winning Iowa and South Carolina and Clinton, 60, winning New Hampshire and Nevada.
Both candidates criticized the 71-year-old McCain, citing his comment U.S. troops could remain in Iraq for 100 years and his support for extending President George W. Bush's tax cuts from 2001 and 2003 after voting against them at the time.
Clinton, asked about the prospect of another term in the White House for a Clinton after eight years of her husband and 12 years of a member of the Bush family, took aim at both Bushes.
"It did take a Clinton to clean after the first Bush and I think it might take another one to clean up after the second Bush," she said at the Kodak Theatre in Los Angeles.
It was the first debate since last week's fierce South Carolina showdown, which featured harsh personal attacks between the two senators that sparked a week of bitter accusations by Obama, Clinton and Clinton's husband, former President Bill Clinton.
They eased off the attacks after Obama's South Carolina win and clearly decided it was better to stay positive in Thursday's debate.
The pair burst into smiles at the suggestion they run for president and vice president on an "Obama-Clinton or a Clinton-Obama ticket."
"Obviously there's a big difference between those two," Obama said, adding how much he respected the former first lady. "I'm sure Hillary would be on anybody's short list."
Obama, an early opponent of the Iraq war, questioned her 2002 Senate vote to authorize the war. He assailed Clinton's frequent comment she has the experience to lead from "day one" in the White House.
"Part of the argument that I'm making in this campaign is that it is important to be right on day one," he said.
Both candidates pointed to health care as one of their biggest policy differences. Clinton's plan requires all Americans to have coverage, and she criticized Obama's plan because it could leave up to 15 million people uninsured.
"You have to bite this bullet, you have to say 'Yes, we will try to get to universal health care'," she said.
Obama said anyone who wanted health care could get it under his plan, which would focus on bringing down costs.
The debate was their first since Obama crushed Clinton and John Edwards in a South Carolina landslide on Saturday, driving Edwards from the race. Both Clinton and Obama praised Edwards in their opening statements.
Earlier on Thursday, popular California Gov. Arnold Schwarzenegger endorsed McCain, boosting the Arizona senator's drive to gain his party's nomination for the White House.
"He is a great American hero and an extraordinary leader. This is why I am endorsing him to be our next president of the United States," the actor-turned-politician said.
California is the largest prize among the states that hold nominating contests on "Super Tuesday." McCain, the Republican front-runner, already leads state polls over former Massachusetts Gov. Mitt Romney.
Obama reported he raised $32 million in the month of January alone, matching his biggest three-month fundraising haul of the year and helping him pay for new ads in a half-dozen states that hold contests after "Super Tuesday."
(For more about the U.S. political campaign, visit Reuters "Tales from the Trail: 2008" online at http:/blogs.reuters.com/trail08/)