Santorum’s wins knock Gingrich out of the running in Louisiana

Following last night's big wins in Alabama and Mississippi, Rick Santorum has delivered the knockout blow to Newt Gingrich that he has long desired. Gingrich may or may not actually drop out of the race in the next few days, but he is no longer a viable alternative to Santorum in the anyone-but-Romney vote.

Our predictions in Illinois and Louisiana reflect the new two-person nature of the race for the Republican nomination. Over the last few hours, Gingrich, who had respectable odds in Louisiana going into Tuesday, has fallen out of the race. Santorum is now heavily favored to carry the state at 84.9 percent, according to the political prediction markets. Illinois has always been a two-person race between Santorum and Romney; Romney is favored at 72.7 percent.

Sources: Betfair and Intrade

This article carries the standard caveat that Romney is still the heavy front-runner to gain the nomination; he is currently 85.2 percent likely to win. Romney's surprising difficulty in closing out the race may affect the Republican platform, but it is extremely unlikely to be enough to stop him from gaining the nomination.
David Rothschild is an economist at Yahoo! Research. He has a Ph.D. in applied economics from the Wharton School of Business at the University of Pennsylvania. Follow him on Twitter @DavMicRot and email him at thesignal@yahoo-inc.com.

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