So there are two new data points today validating the idea that Bernie Sanders is becoming a credible threat to Hillary Clinton’s presidential nomination. The first is that upwards of 10,000 people showed up for a Sanders speech in Madison, Wisconsin, which is almost certainly the largest crowd of the cycle so far. The second is a Quinnipiac poll of Iowa showing Clinton’s recently-vast lead over Sanders among likely Caucus-goers shrinking to 19 points (52/33).

I don’t personally think crowd sizes inherently matter a lot, especially in an ideological hothouse like Mad-town where labor folk really know how to organize an event. And we all know the perils of reading too much into early horse-race polls. But unmistakably, the Sanders thing is becoming more than a nuisance to HRC, if only because a lot of media folk are impressed by big crowds and do place a lot of stock in early horse-race polls.

So just for grins, let’s consider what would happen if this continues and HRC appears to be in serious danger of losing in IA and/or NH. Will Bernie-mania spread from sea to shining sea? Could he actually be the Democratic nominee?

Anything’s possible, but I’d say three other scenarios are a lot more likely. One is that alarm over a 75-year-old self-described socialist being the Democratic nominee in a critical election year creates a massive stampede of money and support into HRC’s camp that reboots her candidacy. Reinforcing that scenario is the reality that the landscape for Sanders gets a whole lot tougher after Iowa, whose caucus system amplifies liberal activist and union influence, and New Hampshire, a state that knows Bernie well as a next-door neighbor. Ideology aside, the complexion of Democratic primary voters after NH gets a whole lot less lily-white, and Sanders has no demonstrated appeal to minority voters, while HRC has quite a bit (the belief that minority voters are more ideologically left-bent than other Democrats is one of the great illusions of progressive politics, dashed again and again). For one thing, you can be certain the current occupant of the White House, who has a pretty strong minority following, isn’t going to stand by idly as Bernie Sanders moves towards the nomination.

The second and third scenarios play on the same limitations of Bernie’s appeal. One is that a wounded HRC is supplanted by another “establishment” candidate, and another is that a spent Sanders is supplanted by a more electable lefty figure. You can fill in lots of names in either category. And perhaps Bernie would be perfectly happy serving as the Gene McCarthy of 2016, creating an entirely different competition (though it’s worth remembering Hubert Humphrey ultimately won the 1968 presidential nomination and Nixon won the presidency) than anyone expected.

More likely HRC will use the Sanders threat to rally languid Democrats to her flag and keep the muscle-tone of her campaign taut. But it sure looks like those who were so anxious a few months ago about the need to “keep Hillary honest” are getting their wish.

Ed Kilgore

Ed Kilgore is a political columnist for New York and managing editor at the Democratic Strategist website. He was a contributing writer at the Washington Monthly from January 2012 until November 2015, and was the principal contributor to the Political Animal blog.