Washington (CNN)A new GOP candidate is leading the Republican pack this week's CNN Political Prediction Market -- Marco Rubio.
Political Prediction Market: Marco Rubio leads
For the first time, the Florida senator's odds are higher than former Florida Gov. Jeb Bush's and businessman Donald Trump's. Rubio stands with odds of 29% to win the Republican nomination, according to the game.
Bush is second at 27% odds to win the nomination and Trump is at third place with his chances at 14%.
Before the CNN debate on September 16, Rubio was at a 9% chance to win the nomination. At the end of the debate, his odds shot to 15%. The week after the debate, his chances went from 15% to 25% by September 24. And his odds have fluctuated between 22% to 30% since then.
CNN's Political Prediction Market is a live online prediction game administered by a company called Pivit that factors polls and other factors, including input from online players.
Odds in the game will change as the public weighs in on the increasing or decreasing chance that a candidate or party wins an election. Players can forecast when the odds will change and compete to the top of the leader board.
In addition to the GOP candidates' odds, the first Democratic debate hosted by CNN is next week, which will likely shift the odds for the Democratic candidates.
Vice President Joe Biden's odds continue to increase in the game, now with a 19% chance of winning the Democratic nomination. He is ranked second to front-runner Hillary Clinton, who has a 69% chance for the nomination.
Biden has not announced whether he will seek the Democratic nomination and is likely not going to join the CNN Democratic debate.
CORRECTION: An earlier version of this story misstated the date of CNN's Republican presidential debate. It was on Sept. 16.