[FiveThirtyeight] Twelve years ago, in August 2003, Joe Lieberman led in most polls of the Democratic primary. Eight years ago, in August 2007, Rudy Giuliani maintained a clear lead in polls of Republicans, while Hillary Clinton led in polls of the Democratic nomination contest. Four years ago, in August 2011, Mitt Romney began with the lead in polls of Republican voters, but he would be surpassed by the end of the month by Rick Perry, the first of four Republican rivals who would at some point overtake Romney in national polling averages.
Lieberman, Clinton, Giuliani and Perry, as you've probably gathered, are not the faces atop Mount Rushmore. Only Clinton came close to winning the nomination.
But the problem isn't just that the national polls at this stage in the race lack empirical power to predict the nomination; it's also that they describe a fiction. I don't mean to suggest that Donald Trump's support in the polls is "fake." I have no doubt that some people really love him or that he'd be the favorite if you held a national, winner-take-all Republican primary tomorrow. However, the "election" these polls describe is hypothetical in at least five ways:
They contemplate a vote today, but we're currently 174 days from the Iowa caucuses.
They contemplate a national primary, but states vote one at a time or in small groups.
They contemplate a race with 17 candidates, but several candidates will drop out before Iowa and several more will drop out before the other states vote.
They contemplate a winner-take-all vote, but most states are not winner-take-all.
They contemplate a vote among all Republican-leaning registered voters or adults, but in fact only a small fraction of them will turn out for primaries and caucuses.
This is why it's exasperating that the mainstream media has become obsessed with how Trump is performing in these polls.
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