On Super Tuesday, March 1, 25 percent of the delegates to the Republican national convention will be awarded. If the mainstream field hasn’t been narrowed by that point, it will become very hard to avoid serious damage to the candidate who ultimately emerges as the party’s anointed favorite. The top mainstream candidate could easily fall more than 100 delegates short of what he might have earned in a winnowed field. He would even be in danger of earning no delegates at all in several of the largest states because of one number: 20 percent.

That’s the threshold for earning delegates in Texas, Tennessee, Georgia, Alabama and Vermont, which combine to award 57 percent of the delegates on Super Tuesday and 14 percent of all of the delegates in the Republican race. If candidates don’t get 20 percent of the vote, they get no delegates (unless they finish in the top two of a congressional district, in which case they get a delegate). Oklahoma and Arkansas, worth an additional 13 percent of Super Tuesday delegates, have a 15 percent threshold.

It is easy to imagine how none of the mainstream candidates pass this threshold. None reached 20 percent of the vote in New Hampshire; they’re failing to reach 20 percent in South Carolina polls; and they might fall short again on Super Tuesday if the field doesn’t narrow further.

Worse still for them, a quirk in the rules would send the delegates forfeited by the mainstream candidates straight to Donald Trump and Ted Cruz.