Santorum Quits

Conservative challenger Rick Santorum announced Tuesday that he is suspending his Republican presidential campaign after a weekend of "prayer and thought," effectively ceding the GOP nomination to front-runner Mitt Romney.

Santorum made his announcement after the weekend hospitalization of his 3-year-old daughter Isabella, and in the face of tightening poll numbers in Pennsylvania -- the state he represented as a U.S. senator -- ahead of the April 24 primary.

"Ladies and gentlemen, we made the decision to get into this race around our kitchen table, against all the odds," Santorum told a news conference, flanked by emotional family members. "We made a decision over the weekend that while the presidential race for us is over, and I will suspend my campaign effective today, we are not done fighting."