Tuesday was another pretty good day of polling for Donald Trump. It’s also not an easy day to characterize given the large number of polls published. You could cherry-pick and point to the poll that has Trump up 7 percentage points in North Carolina, for example, or the ABC News/Washington Post national tracking poll that has Trump up 1 point overall. And you could counter, on the Hillary Clinton side, with a poll showing her up by 11 points in Pennsylvania, or a national poll that gives her a 9-point lead.

Our model takes all this data in stride, along with all the other polls that nobody pays much attention to. And it thinks the results are most consistent with a 3- or 4-percentage point national lead for Clinton, down from a lead of about 7 points in mid-October. Trump remains an underdog, but no longer really a longshot: His Electoral College chances are 29 percent in our polls-only model — his highest probability since Oct. 2 — and 30 percent in polls-plus.

Whenever the race tightens, we get people protesting that the popular vote doesn’t matter because it’s all about the Electoral College, and that Trump has no path to 270 electoral votes. But this presumes that the states behave independently from national trends, when in fact they tend to move in tandem. We had a good illustration of this in mid-September, when in the midst of a tight race overall, about half of swing state polls showed Clinton trailing Trump, including several polls in Colorado, which would have broken Clinton’s firewall.

This time around, we haven’t seen too many of those polls in Clinton’s firewall states, such as Colorado, Pennsylvania, Wisconsin and Michigan. But that’s misleading, because we haven’t seen many high-quality polls from those states, period! We have seen lots of polls from North Carolina and Florida — for some reason, they get polled far more than any other states — and plenty of them have shown Trump gaining ground, to the point that both states are pure toss-ups right now.

So, should you expect to see polls showing Clinton behind in states like Colorado and Wisconsin? Not necessarily. Clinton probably still leads in those states, and we’d expect her to win them if she wins nationally by 4 points or so, where national polls have the race.

Here’s an illustration of that. From a set of simulations the polls-only model ran earlier this evening, I pulled the cases where Clinton won the national popular vote by 3 to 5 percentage points. In other words, we’re positing that the national polling average is about right, and seeing how the results shake out in the states:

STATE ELECTORAL VOTES PROJECTED MARGIN TRUMP WIN PROBABILITY (%) Clinton “firewall” (272 EV) New Mexico 5 -7.7 6 Maine 2 -7.5 12 Virginia 13 -6.3 3 Minnesota 10 -5.7 6 Wisconsin 10 -5.0 7 Michigan 16 -4.8 7 New Hampshire 4 -4.6 17 Pennsylvania 20 -4.6 8 Colorado 9 -4.1 10 _ Other competitive states Nevada 6 -1.2 37 North Carolina 15 -0.4 46 Maine CD-2 1 -0.3 48 Florida 29 -0.3 47 Ohio 18 +1.2 66 Arizona 11 +1.6 68 Iowa 6 +1.6 68 Nebraska CD-2 1 +3.5 64 Georgia 16 +4.9 92 Alaska 3 +5.9 75 Utah 6 +8.9 77 Trump has (almost) no path if he loses the popular vote by 3-5 points

Trump’s chances are slim-to-none in this scenario. His odds are 10 percent or below in all of the Clinton firewall states except for Maine and New Hampshire — both of which our model considers more uncertain than other states for a variety of reasons. And Maine wouldn’t be enough to put Trump ahead anyway. Sure, there’s the chance that the polling in one of the other states could be wacky (maybe there’s an unexpectedly high Gary Johnson vote in Colorado, for instance). But if that happens, Clinton has some backup options in the form of Florida, North Carolina and Nevada. She’d have to get really unlucky to lose the Electoral College with a popular vote lead like the one she has now.

But the thing is, this doesn’t really have anything to do with an intrinsic advantage for Clinton in the Electoral College, or Trump’s lack of a path to 270 electoral votes. It’s just saying that if the polls are about right overall — even if they’re off in some individual states — Clinton will win. We agree with that, and that’s why Clinton’s a favorite in our model overall. The polls have her ahead.

The question is how robust Clinton’s lead would be to a modest error in the polling, or a further tightening of the race. So here’s a second set of simulations, drawn from cases in which Trump or Clinton win the national popular vote by less than 2 percentage points:

STATE ELECTORAL VOTES PROJECTED MARGIN TRUMP WIN PROBABILITY (%) Clinton “firewall” (272 EV) New Mexico 5 -4.1 20 Maine 2 -3.0 32 Virginia 13 -2.7 21 Minnesota 10 -1.8 31 Wisconsin 10 -1.0 37 Pennsylvania 20 -1.0 39 Michigan 16 -1.0 38 Colorado 9 -0.3 46 New Hampshire 4 -0.3 48 _ Other competitive states Nevada 6 +2.6 73 North Carolina 15 +3.3 83 Florida 29 +3.7 86 Maine CD-2 1 +4.1 68 Ohio 18 +5.1 92 Arizona 11 +5.4 91 Iowa 6 +5.6 91 Nebraska CD-2 1 +7.1 74 Georgia 16 +8.2 98 Alaska 3 +9.5 84 Utah 6 +11.6 82 Trump has many paths if the popular vote is within 2 points

This isn’t a secure map for Clinton at all. In a race where the popular vote is roughly tied nationally, Colorado and New Hampshire are toss-ups, and Clinton’s chances are only 60 to 65 percent in Wisconsin, Michigan and Pennsylvania. She has quite a gauntlet to run through to hold her firewall, and she doesn’t have a lot of good backup options. While she could still hold on to Nevada, it doesn’t have enough electoral votes to make up for the loss of Michigan or Pennsylvania. And while she could win North Carolina or Florida if polls hold where they are now, they’d verge on being lost causes if the race shifts by another few points toward Trump. In fact, Clinton would probably lose the Electoral College in the event of a very close national popular vote.

It’s true that Trump would have to make a breakthrough somewhere, by winning at least one state in Clinton’s firewall. But that’s why it’s not only reasonable but 100 percent strategically correct for Trump to be campaigning in states such as Michigan and Wisconsin. (I’ll grant that New Mexico is more of a stretch.) Sure, Trump’s behind in these states, but he has to win somewhere where he’s behind — or he’s consigning himself to four more years in Trump Tower instead of the White House. Michigan and Wisconsin are as reasonable as any other targets: Trump isn’t any further behind in them than he is in higher-profile battleground states such as Pennsylvania, and the demographics are potentially more favorable for him.

If you want to debate a campaign’s geographic planning, Hillary Clinton spending time in Arizona is a much worse decision than Trump hanging out in Michigan or Wisconsin. Sure, she could win the state — but probably only if she’s having a strong night nationally. If the results are tight next Tuesday instead, Michigan and Wisconsin are much more likely to swing the election.

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