Santorum takes heavy fire in Arizona Republican debate

Obama urges corporate tax cut, closing loopholes

Assad forces renew barrage on Syria's Homs

Fitch downgrades Greece on debt swap plan

Congress members threatened with biological attack

Judge strikes down law mandating sale of

Home resales at 1-1/2 year-high, supply falls

Iran defiant as U.N. nuclear talks fail

U.S. advisers back experimental obesity pill

Japan cuts in Iran crude imports could be over 20 percent