Democratic rivals turn up rhetoric in heated battle

Washington: Democratic presidential candidates Barack Obama and Hillary Clinton turned up the rhetoric in their increasingly heated presidential primary battle as she issued a new debate challenge and he complained of a race that has largely been reduced to trivia while workers feel economic pain.

Clinton took the debate dispute to a new level, challenging Obama to face off with her in a debate without a moderator.

Indiana campaign

"Just the two of us, going for 90 minutes, asking and answering questions, we'll set whatever rules seem fair," Clinton said Saturday while campaigning in South Bend, Indiana.

Her campaign made the offer formal with a letter to the Obama campaign.

Obama aides said he had already debated Clinton 21 times, "the most in primary history."

"Over the next ten days we believe it's important to talk directly to the voters of Indiana and North Carolina," said Obama spokesman Robert Gibbs.

Trailing in delegates and the popular vote, Clinton has been stepping up the pressure on Obama for more debates in advance of primaries in nine days in Indiana and North Carolina.

Clinton argued that Obama won't debate because he's unhappy with questions from TV moderators during the April 16 debate just before the Pennsylvania primary.

After that debate, Obama complained it focused too much on political trivia and too little on real issues like working families suffering from economic pain.

On the campaign trail Saturday, he sounded much the same theme.

"If you watched the last few weeks of this campaign, you'd think that all politics is about is negative ads and bickering and arguing, gaffes and sideline issues," Obama said.