Rick Santorum won the Alabama and Mississippi primaries last night, surprising the political world and dealing a major setback to the campaigns of Newt Gingrich and Mitt Romney.

“We did it again,” Mr. Santorum said, addressing jubilant supporters in Louisiana, which holds its Republican primary next week. “The time is now for conservatives to pull together.”

Mr. Gingrich noted that he walked away with nearly as many delegates as the others and pledged to take his candidacy to the Republican convention in August.

“The elite media’s efforts to convince the nation that Mitt Romney is inevitable just collapsed,” Mr. Gingrich said, addressing a subdued crowd here in Birmingham. “If you’re the front-runner and you keep coming in third, you’re not much of a front-runner.”