Yesterday, I wrote about the middle and upper echelons of the Democratic field: those candidates who are polling in the mid-single-digits or higher. You can certainly posit a rough order of which of these candidates are more likely to win the nomination. I’d much rather wager a few shekels on Joe Biden than Pete Buttigieg, for instance. But I don’t think there’s any hard-and-fast distinction between the top tier and the next-runners-up.

For candidates outside of that group — those polling in the low single digits, or worse — I have less-welcome news. I don’t really care which order you place them in, because unless they turn it around soon, they’re probably toast.

In this article, I’m mostly referring to Cory Booker, Beto O’Rourke, Julián Castro and Amy Klobuchar, who I’ll refer to as the BOCK candidates (Booker/O’Rourke/Castro/Klobuchar) for short. Some of this also applies to candidates (e.g. Michael Bennet) who didn’t make this week’s debate at all, although they’re in even worse shape. I’m not counting Andrew Yang as part of this group, however. He’s actually polling slightly better than the BOCKs, despite lower name recognition, and is more of a sui generis case.

Subjectively speaking, the BOCK group is a reasonably interesting and well-qualified set of candidates. At times, I’ve thought various members of this group were poised for a breakout. (I also thought some of them, such as Klobuchar, would come out of the gate stronger when they initially launched their campaigns.) If you fast-forwarded to next July and one of these candidates — Booker, say — was accepting the Democratic nomination in Milwaukee, it wouldn’t be that surprising on some level. They have the sort of profile that resembles those of past presidential nominees.

But the BOCK candidates don’t have the polling of those past nominees. And empirically, that’s a pretty enormous problem for them. As my colleague Geoffrey Skelley discovered in his series on the predictive accuracy of early primary polls, only one candidate in the modern primary era has come back from averaging less than 5 percent in national polls in the second half of the year before the primary to win the nomination. That was Jimmy Carter, who did so in 1976. Given the number of candidates who failed to make it, that would make their chances of winning the nomination very low — somewhere on the order of 1 or 2 percent.

Now, you might look at someone like a Booker or a Klobuchar and assume that they’re better qualified than the candidates who were polling in the low single digits in past nomination races. But that’s not necessarily true. Sure, those races included plenty of Alan Keyeses and Dennis Kuciniches, but there were also plenty of other senators and governors who were highly plausible nominees but whose campaigns just never really gained traction.

Of course, there are a few caveats and qualifications. Geoffrey’s research covers polling across the entire second half of the pre-election year — that is, from July through December. If Booker or Klobuchar began surging in the polls now, they could finish above that 5 percent threshold over the six-month period. Also, these candidates are running full-fledged campaigns, whereas some of the low-polling names from past nomination cycles spent a lot more time flirting with whether to run or not. Meanwhile, Booker and Klobuchar (more so than O’Rourke or Castro) have decent numbers of endorsements, which are historically a fairly predictive indicator, although most of those endorsements are from their home states.

So, if you want to go to the mat and argue that Booker or one of the other BOCK candidates has, I don’t know, a 5 percent chance of winning the nomination, I’m not really going to argue with you. (And collectively, they have a better chance than they do individually, of course. Keep that in mind if you’re hate-reading this column a year from now because O’Rourke won the nomination or something.)

But a lot of this smacks of special pleading, and ignores that the empirical evidence is fairly robust in this case: Lots of candidates have hoped to come back from polling in the low single digits to win their nominations, and almost none of them have done it. A somewhat larger group have emerged as factors in races that they ultimately didn’t win — Rick Santorum in 2012, for example — but elections aren’t something where close really counts. Nor are any of these candidates polling especially well in Iowa or New Hampshire, which is the path that dark-horse candidates (such as Carter or Santorum) usually take to enter the top tier.

It’s also pretty hard to know what type of event might trigger a sudden surge in support for one of the BOCKs. Castro and Booker had strong nights in the first and second debates, respectively, and it barely moved the numbers for them. O’Rourke saw a spike in media attention following the mass shooting in his home town of El Paso, Texas, and his support in polls didn’t move much after that, either.

Moreover, Democrats are fairly satisfied with their field, and they’re paying a relatively large amount of attention to the campaign as compared with similar stages in past nomination races. That’s also a bearish indicator for the BOCKs. Democrats aren’t necessarily shopping around for fresh alternatives, in the way that Republicans were in 2011 and 2012, when Santorum, Newt Gingrich, Herman Cain and others surged and declined in the polls.

That may be because the top three to five candidates do a relatively good job of covering the various corners of the Democratic primary. College-educated voters tend to like Elizabeth Warren, Kamala Harris and Buttigieg; non-college voters have Biden and Bernie Sanders. Older voters tend to like Biden, whereas Sanders’s and Warren’s supporters are younger. Moderates have Biden, while liberals have lots of alternatives. Biden is well-liked among black voters, and if they sour on him, there’s Harris. Hispanic voters don’t have an obvious first choice, and maybe there’s a niche for a moderate candidate who isn’t Biden for voters who think Biden is too old. But overall, the Democratic electorate is pretty well picked over.

Put another way, if you’re wondering why candidates such as Castro and Booker aren’t gaining more traction despite seemingly having run competent campaigns, the answer may have less to do with them and more to do with the fact that the field has a lot of heavyweights. Biden is a former two-term vice president; Sanders was the runner-up last time and basically built an entire political movement, and Warren and Harris have been regarded as potential frontrunners since virtually the moment that Donald Trump won the White House. The years that produce volatile, topsy-turvy nomination races, such as the 1992 Democratic primary, tend to be those where a lot of top candidates sit out, perhaps because they’re fearful of running against an incumbent with high approval ratings. Trump looks beatable, however, and almost all of the highly plausible Democratic nominees, save Sherrod Brown, ran. There isn’t much oxygen for those at the top of the field, let alone for the candidates a few rungs down.





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