Clinton gets caustic, Obama sarcastic

She questions experience -- he wonders what hers is

KNOXVILLE, Iowa -- The economy needs help and fast, Hillary Rodham Clinton declared Monday, claiming the experience for the job and saying the nation can't afford to break in a newcomer.

Without mentioning names, she suggested Democratic rival Barack Obama -- less than three years into his first term in the Senate -- and other candidates lack the experience necessary to address the nation's fiscal challenges.

''There is one job we can't afford on-the-job training for -- our next president. That could be the costliest job training in history,'' Clinton said.

Obama offered a sharp response.

''My understanding is she wasn't Treasury secretary in the Clinton administration. I don't know exactly what experience she's claiming,'' he said. ''Rather than just assert experience, if she has specific differences with me in regard to economic policy then let's have that debate.''

Clinton, in her speech, also tackled the issue of Social security. In recent weeks, Clinton and Obama have traded barbs over the retirement program. AP