Romney and Santorum swap charges in 20th debate (AP)

Poll: Obama benefitting from improving economy (AP)

Shelling kills 2 Western journalists in Syria (AP)

Newark mayor: NYPD Muslim files 'deeply offensive' (AP)

2nd degree murder verdict in lacrosse death trial (AP)

Police: Girl forced to run 3 hours dies; 2 charged (AP)

Teenage girl dies after inhaling helium at party (AP)

Police say love triangle led to CA murder-suicide (AP)

Cowell: 'X Factor' wants 2 female judges, 2 hosts (AP)

Man's childhood comic collection fetches $3.5M (AP)

Santorum at center stage in Arizona Republican debate (Reuters)

Obama urges corporate tax cut, closing loopholes (Reuters)

Assad forces renew barrage on Syria's Homs (Reuters)

Fitch downgrades Greece on debt swap plan (Reuters)

Congress members threatened with biological attack (Reuters)

Judge strikes down law mandating sale of (Reuters)

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

Iran defiant as U.N. nuclear talks fail (Reuters)

Could Rick Santorum super PAC do more harm than good? (The Christian Science Monitor)

Stolen Valor Act at Supreme Court: Is lying about being a hero a right? (The Christian Science Monitor)