Clinton, Obama toughen their attacks

By Claudia Parsons

PROVIDENCE, R.I., Feb 24 (Reuters) - Democratic presidential hopefuls Hillary Clinton and Barack Obama sharpened their attacks on each other on Sunday as they headed for showdowns in Texas and Ohio on March 4.

Clinton, who trails Illinois Sen. Obama in delegates to this summer's national convention that will pick the Democratic candidate for the November election, needs wins in both Texas and Ohio to keep her campaign afloat.

"I'm working as hard as I can," the New York senator told reporters in Rhode Island, which also votes on March 4. "I have good campaigns in Texas and Ohio and I feel really positive about what's going to happen on March 4."

The former first lady, who would be the first woman U.S. president, toughened her attacks on Obama and some leaflets he circulated in Ohio criticizing her health care plan and past support for the North American Free Trade Agreement.

"Nobody believes Senator Obama's plan is universal because it's not. Mine is," she said in Rhode Island, which also votes on March 4. "So raise legitimate questions but don't engage in, you know, this kind of false and misleading advertising."

"There's a big difference between what is said in that campaign and what is done in that campaign," she said.