Hillary Clinton slammed rival Barack Obama on Saturday for campaign leaflets on her health-care plan that she called "blatantly false" and accused him of using Republican tactics in their contest for the Democratic US presidential nomination.

Democratic presidential hopeful New York Senator Hillary Clinton speaks to supporters at an early voting event in Dallas, Texas, February 22, 2008. Clinton launched a scathing attack on Democratic rival Barack Obama Saturday in a bid to restore her front-runner status ahead of key nominating contests next month. [Agencies]

In a bitter exchange, Obama defended the leaflet as accurate and campaign spokesman Bill Burton decried Clinton's "negative campaign."

"Shame on you, Barack Obama," Clinton said, speaking to reporters after a rally in Ohio, a state that is key to her struggling campaign.