Wednesday night's Democratic debate may be most remembered for Michael Bloomberg getting absolutely mauled. But the most revealing moment came toward the end when it became clear that none of Vermont Sen. Bernie Sanders's Democratic rivals are very confident that they can stop him from winning the most delegates, and their strategies now largely hinge on their hopes of stopping him at the Democratic convention.

NBC's Chuck Todd asked a straightforward question of all six candidates on stage: If at the end of all the primaries none of them receive the outright majority of the delegates needed to clinch the nomination on the first ballot, should the candidate with the most delegates be the nominee?

Sanders was the only one onstage who said he believed the nomination should go to the candidate who wins the most delegates, which signals his increasing level of confidence ahead of another expected win in Nevada that should cement his front-runner status with Super Tuesday quickly approaching.

Sens. Amy Klobuchar of Minnesota and Elizabeth Warren of Massachusetts, Joe Biden, Michael Bloomberg, and Pete Buttigieg all said that they would want to let the convention process play itself out. That suggests that none of the candidates are very confident that they will amass more delegates than Sanders. Instead, they are hoping that if enough of them win a sufficient number of delegates, they could at least deny him a majority, and then fight things out on the convention floor.

Though the idea of a contested convention is a long-standing fantasy of political junkies that has not come to fruition in the modern political era, there are a number of reasons why the possibility is more likely this year.

One is that Democrats have a proportional allocation system. Unlike the Republican primaries, in which a front-runner can rapidly gather delegates in winner-take-all states, in the Democratic system, multiple candidates can win delegates by winning more than 15% of the vote either statewide or in individual congressional districts.

Adding to that, this time around Democrats have had a large and fractured field and a high concentration of primaries early on when the field has not had enough time to consolidate. California, which alone has about one-fifth of the delegates needed for the Democratic nomination, used to be one of the last states to vote, often helping to put the nominee over the top toward the end. But now it votes on March 3 with other Super Tuesday states, and so the front-runner will have to split the huge haul with multiple candidates.

Another complicating factor is that under a rules change, superdelegates (or officeholders and party officials who get to vote for whoever they want) are no longer allowed to put any candidate over the top on the first ballot.

Right now, Sanders is the clear front-runner, but there are a number of candidates who have the ability to absorb delegates. Bloomberg, hoping to prevent a Sanders nomination, obviously has as much money to stay in as long as he wants. Buttigieg has also raised a significant amount of money, and his strong performance in Iowa and New Hampshire will justify his staying in the race for a while. Even if he doesn't make inroads among black voters, he can still keep vacuuming up delegates in heavily white states and congressional districts. If Biden still has some residual strength among black voters, he can further carve into the pot of delegates. And so on.

Though one can see various paths for candidates to remain viable enough to continue winning some delegates, right now, it isn't clear that any of the candidates have a strategy for stopping Sanders from winning a lot of states and racking up the most number of delegates. That puts them in the precarious position of hoping to take him down on the convention floor.

However, this is easier said than done. Were Democrats to deny Sanders the nomination after he wins the most delegates, they risk a massive backlash that could make it harder for the ultimate nominee to convince Sanders voters to show up in November.