Hillary Clinton, defending her husband's increasingly vocal role in her presidential effort, sidestepped questions about whether Bill Clinton's suggestion that Barack Obama had put a "hit job" on him was language befitting a former president.

Video | Results | Slideshow | Newsletter

"We're in a very heated campaign, and people are coming out and saying all kinds of things," Hillary Clinton said in an interview Wednesday. "I'm out there every day making a positive case for my candidacy. I have a lot of wonderful people, including my husband, who are out there making the case for me."

The former president suggested that his wife may lose Saturday's Democratic primary because many black voters will side with Obama. The unusually direct comment on the possible role of race in the election was in keeping with the Clintons' bid to portray Obama as the clear favorite, thereby lessening the potential fallout if it proves true.

Voting for president along racial and gender lines "is understandable, because people are proud when someone who they identify with emerges for the first time," the former president told a Charleston audience Wednesday while campaigning for his wife, a role he has played all week.

His comments and a later outburst with a reporter came on a day when Obama continued to challenge Hillary Clinton's candor and trustworthiness. He said his chief rival has indulged in double-talk on bankruptcy laws, trade and other issues.

The atmosphere grew more charged after Clinton's campaign aired a radio ad in South Carolina suggesting Obama approved of Republican ideas. Obama responded with his own radio spot that says, "Hillary Clinton will say anything to get elected."

Bill Clinton, campaigning on the coast Wednesday while Obama was inland, said Obama and the media had stirred up tensions over race in response to some Democrats' criticisms of the couple's strategies.

"I never heard a word of public complaint when Mr. Obama said Hillary was not truthful," and had "no character, was poll-driven. He had more pollsters than she did," the ex-president said in a heated exchange with a CNN reporter. "When he put out a hit job on me at the same time he called her the senator from Punjab, I never said a word."

The former president had reacted angrily upon being told that Dick Harpootlian, a former South Carolina Democratic chairman and Obama supporter, had called the Clinton campaign "reprehensible" and suggested it had borrowed tactics from Lee Atwater, the late South Carolina GOP strategist who famously practiced negative campaigning.

It was not clear what Clinton meant by "hit job." Hillary Clinton refused to speculate in the interview.

"He was thinking about something. You'll have to ask him what he means," she said, while calling the comparison to Atwater "outrageous."

"Talking about people's records? Talking about what they do in the campaign? That's fair game. That's what we do in America,"

Clinton Readies Economic Speech

The former first lady's comments came as she readied a speech on ways to halt the global economic slide and stabilize U.S. financial markets. She previewed the speech in an interview with The Associated Press.

The New York senator planned to call Thursday for immediate steps to address the U.S. housing crisis.

Clinton said the rapid rise of home foreclosures stemming from subprime mortgages had rocked global markets like no other factor. Proposed tax rebates to stimulate the U.S. economy - including those championed by Obama - were necessary but not sufficient, Clinton said.

"It's OK, I'm for tax rebates - put some money in people's pockets, though it has to be structured in right way," Clinton said. "But all the talk of stimulus and all the planning going on with Congress and the White House is going to miss the boat if we don't stem the tide of foreclosure."

Clinton, who came late to the notion of such tax rebates as economic stimulus, said she had been initially been reluctant to reopen the tax code.

"But the situation deteriorated quickly," she said, which meant any agreement would have to include tax rebates.

"I want to emphasize the urgency of the situation we find ourselves in," Clinton said, saying South Carolina has a particularly complex set of economic challenges including home foreclosures, payday lending problems and higher than average level of student debt.

"When I started warning about this housing crisis and what it would do to the economy, I was blown off. I couldn't get any attention," Clinton said. "Republicans and others said, 'You're an alarmist, it's not a big deal."'

Clinton's plan to freeze home foreclosures for 90 days has been criticized by some economists who have said it would raise home interest rates across the board while unfairly favoring consumers who had gotten into risky mortgages.

Clinton rejected that argument.

"People will say, 'Why should we bail out somebody who made a bad loan?"' she said. "Because you don't want a vacant house next to you. You don't want a deteriorating neighborhood. You don't want a tax base dropping so police service to your home gets cuts. We're all in this."

Clinton also expressed support for Ben Bernanke, chairman of the Federal Reserve, but declined to say whether she would keep him on as Fed chairman if she is president when his term expires.

"He's walking a very difficult line - I'm not going to second guess him," Clinton said, while saying he probably should have taken action earlier to address the housing crisis.

"I think he inherited a lot of problems he is trying to work through," she said. "He's got to stimulate the economy, to get credit flowing again, and to raise investor confidence. It would have been difficult to predict how dependent the global economy would be on the American consumer."