How many counties will Hillary Clinton win in the 2016 Iowa Caucuses?

[Mr. Morden]

What % of the statewide caucus vote do you actually expect her to get?  And who do you think will still be in the race by caucus day?

Remember that in the Democratic caucus system, at any individual caucus site, if a candidate has less than 15% of the vote at that site, the voters have to reallocate their support to someone else.  So anyone who's polling in the 10-15% range or below statewide is going to get absolutely massacred by this rule, and wind up with very few votes.  (See, e.g., Biden and Richardson polling around 5% each in 2008, but only ending up with ~1-2% in the end.)

Now, one way around this is for candidates to cut deals with each other: At caucus sites where I don't reach viability, I'll ask my voters to back some other candidate, if that candidate asks his voters to do the same.  So that's a way out, if whoever of O'Malley, Sanders, and Webb are still running at that point cut such deals with each other, to prevent a Clinton clean sweep of every county.  But not every voter is going to go along with that.

So, bottom line, Clinton is far more likely to lose some counties if she just faces a single opponent with the consolidated non-Clinton vote, rather than if she faces three opponents each polling at 10-15%.

[Mr. Morden]

Also, a more interesting question may be "Which counties is she most likely to lose?"