The two titans of the Republican presidential contest hammered each other over job creation and Social Security on Wednesday night, as Rick Perry got his first chance to articulate his campaign message on the national debate stage.

The Texas governor sparred early and often with former Massachusetts Gov. Mitt Romney, whom he has overtaken as front-runner since joining the race a month ago. With Perry trying to defend that position and Romney trying to reclaim it, the two came armed with zingers to take each other down a peg.

"Michael Dukakis created jobs three times faster than you did, Mitt,” Perry quipped, in a stinging reference to the former Massachusetts governor who lost the presidential election to George H.W. Bush.

Romney immediately shot back that “George Bush and his predecessors created jobs at a faster rate than you did.”

The critiques were among multiple rapid-fire exchanges between the two candidates, who shared the stage with six other White House hopefuls at the Ronald Reagan Presidential Library in Simi Valley, Calif., a symbolic setting that invoked the memory of the conservative Republican who swept to two terms as president.

The debate also marked a key test for Minnesota Rep. Michele Bachmann, whose prospects rose last month with her win in the Iowa Straw Poll only to be overshadowed by Perry's entrance into the race....