(BIRMINGHAM, Ala.) --ABC projected Rick Santorum would win the Alabama and Mississippi primaries, giving the former Pennsylvania senator high-stakes victories in key Southern contests Tuesday.
Mitt Romney, who still holds a commanding delegate lead for the nomination, trailed in third place behind Newt Gingrich in both races, with majorities of precincts reporting.
Santorum's victories came after a week of polls that showed the three challengers running virtually neck-and-neck in both states, which award delegates on a proportional basis.
Late Tuesday night Romney had 471 delegates, Santorum had 238 and Gingrich had 126 total delegates. A candidate needs 1,144 to secure the nomination.
But the Alabama and Mississippi wins will provide a boost to Santorum, even though he will still be well behind in the race for delegates. Before polls closed Tuesday, Romney said Santorum was "at the desperate end" of his campaign -- a prediction that may prove premature after Tuesday's results.
The candidates did not stick around for results.
"We did it again," Santorum declared at an event in Louisiana. He said that despite Romney's deep campaign pockets, he has won in the Midwest and South and is forcing the Romney campaign back on its heels. He heads to Puerto Rico Wednesday to campaign.
Romney spent the night in Missouri, which holds a state caucus Saturday. Santorum won a non-binding primary there in February.
Gingrich stayed in Alabama to watch the results, which he said dealt a blow to Romney.
"If you're the front runner and you keep coming in third, you're not much of a front-runner," Gingrich said.
Alabama and Mississippi were not the only states holding nominating contests on Tuesday night. Hawaii was also holding caucuses, but final results will not be available until early Wednesday morning and American Samoa was also finalizing the results of its caucuses.
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