March 11 (Bloomberg) -- Democratic presidential candidates Barack Obama and Hillary Clinton kept up their sparring while campaigning today in Pennsylvania even as voters in Mississippi headed to the polls for a primary there.

Obama made a final appeal to Mississippi voters this morning, talking about energy, education and the economy in Greenville, before heading north. Obama, who's vying to become the first black U.S. president, is heavily favored in the state, where more than half of the Democratic electorate is black.

Clinton renewed her line of attack on the Illinois senator's experience and record, telling a crowd of several thousand people in Harrisburg, Pennsylvania, ``There's a big difference between talk and action.''

The former first lady ``will say and do anything to win this election,'' Obama spokesman Bill Burton said in a statement sent to reporters ahead of her speech.

Both campaigns are turning their attention to Pennsylvania, which has 158 pledged delegates available in its primary on April 22 compared with 33 at stake today in Mississippi. Clinton, a senator from New York, trails Obama in the race for Democratic convention delegates, who will select the party's nominee. She has set Pennsylvania as a key test of her campaign.

Labor Support

Clinton stood on stage at a concert hall in downtown Harrisburg with dozens of supporters behind her, including a group representing union workers. She's counting on organized labor to help her score a victory in Pennsylvania, which has lost more than 200,000 manufacturing jobs since 2001.

``I want you to be voting on the basis of who you believe will be our best president, who can be our commander-in-chief from Day One,'' Clinton, 60, said. ``I don't want you voting on a leap of faith, I want you to look at the record, I want you to look at the results.''

She told the audience that the ``eyes of America and the world are on Pennsylvania.''

In Greenville, Mississippi, this morning, Obama, 46, made a campaign stop at Buck's Restaurant, where he ate a breakfast of scrambled eggs, grits, turkey sausage and wheat toast with the town's mayor and other city officials.

They spoke about education and ``clean energy'' jobs, among other topics. As they talked, some in the crowd outside were chanting ``Yes, we can,'' Obama's campaign slogan.

Obama Supporter

Restaurant owner S.B. Buck, 60, said he's supporting Obama over Clinton, even though he thinks the candidate's husband, Bill Clinton, was a great president. Buck, who is black, said he was turned off by some of the tactics used by the Clinton campaign that have injected race into the political debate.

``I think they did more to put people in his corner than take them out,'' Buck said in an interview.

Obama's aides spoke out against statements by Clinton supporter Geraldine Ferraro, a former U.S. representative from New York and the Democratic vice presidential nominee in 1984. In an interview with the Daily Breeze newspaper in Torrance, California, Ferraro said Obama has advanced because of his race.

Ferraro Remarks

``If Obama was a white man, he would not be in this position,'' Ferraro was quoted as saying by the newspaper in a story published March 7. ``And if he was a woman he would not be in this position.''

Obama called the statement ``divisive'' in an interview with the Morning Call newspaper in Allentown, Pennsylvania.

``I don't think Geraldine Ferraro's comments have any place in our politics or in the Democratic Party,'' Obama told the newspaper. ``I think anybody who understands the history of this country knows they are patently absurd.''

Obama's chief strategist, David Axelrod, said Ferraro's remarks are ``part of an insidious pattern'' on the part of Clinton's campaign. He called on Clinton to remove Ferraro from her finance committee and as a campaign surrogate.

Clinton distanced herself from the comments.

``I do not agree with that,'' she told the Associated Press in an interview. ``It is regrettable that any of our supporters on both sides, because we've both had that experience, say things that kind of veer off into the personal. We ought to keep this on the issues.''

An Obama adviser, Samantha Power, resigned last week after she was quoted in a Scottish newspaper calling Clinton ``a monster.''

McCain Campaigns

Senator John McCain of Arizona, who has clinched the Republican presidential nomination, is holding fundraisers this week while campaigning in town-hall-style forums.

In St. Louis today, he promoted his economic agenda and emphasized his understanding that the economy was in a downturn.

``We know that Americans are hurting. We know that these are difficult times,'' said McCain, 71.

He also took shots at Clinton and Obama over their statements that they would begin withdrawing U.S. combat troops from Iraq if elected and would demand that Mexico and Canada agree to modifications to the North American Free Trade Agreement.

Pulling out of Iraq too soon would mean that ``the conflict will spread and we will be back, with greater sacrifices,'' he said.

McCain said an attempt to renegotiate the free-trade agreement with the nation's two neighbors would throw U.S. credibility into question in other treaty talks.

To contact the reporters on this story: Kristin Jensen in Harrisburg, Pennsylvania at kjensen@bloomberg.net; Kim Chipman in Greenville, Mississippi at kchipman@bloomberg.net

Last Updated: March 11, 2008 19:25 EDT