Who won the Republican debate, and who lost? While pundits mayspeculate wildly and focus group polls could offer some insight,according to those willing to put their money where their mouth is,the answer is clear: Marco Rubio won a decisive victory, and JebBush may very well be finished.

PredictIt is a successor to InTrade, which drew major attention during the 2012 presidentialrace before being shut down for dubious financial practices.The site is a so-called “Prediction Market,” whereparticipants bet on future events by buying “shares”that reflect them happening or not happening. When the event isresolved, shares are paid out at $1 apiece if the prediction wasright, but become worthless if the prediction was wrong. As aresult, a share’s price roughly corresponds to anevent’s likelihood of happening, based on the knowledge ofbettors.

PredictIt, then, serves as a useful way of gauging how peoplereally think the GOP race is going. While it’s easy forpundits to say that a candidate is a “lock” for thenomination or utterly doomed, PredictIt and sites like it havetheir odds determined by those willing to put their money wheretheir mouth is.

One of the most popular prediction markets is for the Republican presidential nomination, withhundreds of thousands of shares being traded for the majorcandidates. Wednesday’s debate saw huge swings for severalRepublican candidates.

The biggest winner on PredictIt was Rubio, who saw a huge boost over the courseof the debate as he skillfully parried attacks from the moderatorsand Bush over his personal finances and his Senate attendancerecord. Going into the debate, Rubio’s PredictIt share pricefor winning the Republican nomination stood at 42 cents. ByThursday morning, his share price had soared to 53 cents, beforedropping a bit back to 51 cents. In other words, bettors thinkRubio’s debate performance boosted his odds of winning theRepublican nomination by at least 9 percent, all byitself. (RELATED: Rubio Rattles Jeb: ‘SomeoneConvinced You That Attacking Me Will HelpYou’)

Another Republicans who saw smaller gains during and after thedebate was Chris Christie, who surged fromabout 8 cents to as high as 14 cents.

While Ted Cruz has been touted as Wednesday’s big winnerafter his aggressive criticism of media bias, PredictIt isn’t convinced yet. He went into thedebate with his shares at 21 cents, and while he briefly rose toabout 25 cents this morning, he’s rapidly dropped back downto where he started. Similarly, Ben Carson and DonaldTrump saw little change from their pre-debate odds.

Wednesday night’s big loser? Bush. Despite his many campaign setbacks,PredictIt had remained relatively bullish on Bush’s chances,and he went into the debate with his shares still valued at 28cents, ahead of everybody except Rubio. But after his performance,which included a bungled effort to attack Rubio for his Senateattendance record, bettors rapidly soured on Bush. His sharestumbled all the way down to 11 cents, before recovering somewhatthis morning to about 13 cents as of noon today. Inother words, one bad debate performance has droppedBush’s odds of winning the nomination by about one-half, ifnot more.

The other big loser on PredictIt may be moresurprising. Carly Fiorina went into the debate fluctuatingaround 13 cents, but dropped to just 5 cents in the immediateaftermath before stabilizing at 7 cents. Fiorina’s drop mayreflect a failure to deliver any of the strong blows that made hera media darling after the first and second GOP debates.

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