According to Vox's Kelsey Piper:
I observed above that the primaries are quite a tossup — there are still four candidates with a very reasonable shot at winning. But I still have this feeling they’ll be over quickly. There’s the four early caucuses and primaries: Iowa, New Hampshire, South Carolina, and Nevada. Then on March 3rd, a large, demographically balanced (representing the overall Democratic electorate pretty well) set of states will vote.
Two-person races often drag out well past Super Tuesday. But I think this four-person race might be primed to end pretty fast. Once a candidate has gotten a series of wins, voters might be pretty quick to rally behind them — and a Super Tuesday lead might quickly become insurmountable.
Will the Democratic primary be settled on Super Tuesday?
This question resolves positively if Electionbettingodds.com assigns one candidate at least 90% of winning the Democratic primary at some point within the 7-day period starting on Super Tuesday (Tuesday, 3 March).