But we aren't yet at the end of the race, I regret to inform you. So what can the polls tell us now? And why do they seem so often to be in conflict?

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Let's consider four questions:

Why do national polls show Hillary Clinton with a bigger lead than state polls do?

Why do different poll results vary so much?

We keep hearing that Donald Trump is doing far worse with some demographics than Republicans have in the past, but he still leads in some polls. Why?

How predictive are polls at this point, anyway?

Why do national polls show Hillary Clinton with a bigger lead than state polls do?

We looked at this Wednesday morning. Polling averages from RealClearPolitics in Florida, Ohio and Pennsylvania show much closer races than we see in the national average.

By listing those states, we give the game away a little: Florida and Ohio are well-known swing states. They are usually closer than the rest of the country, just as Texas, New York and California are usually less close than everywhere else.

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And swing states, because they tend to be close, also get more attention from pollsters. Sure, we'll see a few polls from New York and Texas, probably, but we already can guess what those polls will say: Clinton leads in the former and Trump in the latter. So the polls we see the most of tend to be places where the race is closer, which could have the effect of making the race on the whole look closer.

Pennsylvania is not usually a swing state — or, at least, it's been pretty reliably Democratic. As we noted last month, Pennsylvania's been slowly sliding to the middle. (See also this excellent explanation from FiveThirtyEight's Dave Wasserman.) So Trump is doing better against Clinton in Pennsylvania than Mitt Romney did against Barack Obama, but in Arizona the opposite is happening. Swing states aren't constant. What is constant is that close races will see more polling.

Why do different poll results vary so much?

This is a complicated question.

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We explained last year how The Post conducts its polling, which gives some good detail on the process.

But that process varies from pollster to pollster. Those variances can be big: Live phone calls versus Internet-based surveys, for example. The number of people called. They can be smaller: How people are chosen to participate. There are differences at every level of conducting the survey, including in the weighting that happens after all poll respondents have been contacted. Combine those different methodologies with the fact that polls are taken at different times, and variances are to be expected. These are the photos taken from a number of different angles, to go back to our analogy.

Here's what the last month of national polling has looked like in the presidential race.

There are about 40 polls there, using a wide range of methodologies and samples. There's also a wide range of results. Clinton's are between 39 and 51 percent; Trump ranges from 29 to 46 percent. Those figures, though, and a glance at the graph above, make one thing pretty clear: The picture of the horse race we get from this series of photos is that Hillary Clinton is in the lead.

We can overlay the RealClearPolitics polling average to put a fine point on that.

The RCP average (as it's known) doesn't use all of the data points displayed on that graph, but the picture is still the same: Clinton has maintained a pretty consistent lead. She was up 5.5 points June 14; she was up 4.3 points as of July 13, the most recent day for which the average is calculated.

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In short, fluctuations are to be expected. The question is: Are there more fluctuations this year than in general?

The Post's polling guru, Scott Clement, looked at the standard deviation of the polls taken from February to July of 2008, 2012 and 2016.

"National polls this year have shown greater variation in Trump and Clinton's support than polls in 2012 and 2008," Clement told me, "though there hasn't been greater noise in polls' Clinton-Trump vote margin. One reason is that polls range more in their percentage who express no opinion — this is partly a finding of resistance to selecting Clinton or Trump, but also partly due to growing presence of Internet polls where 'no opinion' tends to be explicitly offered as an option."

We've looked at this, too. More people pick an option besides the major-party candidates in recent polls than did in 2004, 2008 or 2012.

We keep hearing that Donald Trump is doing far worse with some demographics than Republicans have in the past, but he still leads in some polls. Why?

Pew Research conducted polling that broke down how Clinton was doing against Trump with various demographic groups relative to how Obama was doing against Romney at this point in the 2012 election cycle. With nearly every group, we learned, Clinton is doing better now than Obama was then — and with some groups, such as white women who have graduated college, she's doing much better.

White women in general are shaping up to reject Trump in a way that we haven't seen in decades. The last time they preferred the Democrat to the Republican in November (according to exit polling) was in 1996. Pew has white women preferring Clinton by 10 points right now. (Pew had them preferring Romney by 6 points four years ago.) No Republican has done that poorly with white women in the 44 years for which we have exit-poll data.

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So how is Trump staying close? Well, we'll point out that he is losing nationally, according to most polls. But then we'll also point out where Trump has gained: with white men.

The graph above shows that while white women with college degrees are 30 points more supportive of Clinton vs. Trump than the group was for Obama vs. Romney, white men are 5 points more supportive of Trump than of Romney. Thirty is bigger than five, obviously — but there are a lot more white men than there are white women with college degrees. There are more white people in America than nonwhite people (defining "white" here as "non-Hispanic white"). So smaller shifts in how they vote have a bigger impact.

But wait, you're thinking, you just said that white men are 5 points more supportive of Trump vs. Clinton than they were Romney over Obama — but white women are 16 points more supportive of Clinton vs. Trump than they were Obama over Romney in Pew's poll! And that's true. Pew also shows a 9-point lead for Hillary Clinton, a much bigger margin than the national polling average (and than many polls).

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Polls that show those historic shifts away from Trump are also more likely to show bigger Clinton leads. Comparing close swing-state polls with something like Pew's results is a bit like comparing one type of fruit to another fruit on qualities specific only to one of the fruits. (There may be an easier way to say this.) [Nah, that works. —Ed.]

How predictive are polls at this point, anyway?

This is the question you came here to have answered, and, because I am a jerk, I made you wait.

The answer is: Sort of.

FiveThirtyEight's Nate Silver made his name by developing a model that would take poll data to forecast a likely outcome. The site has published that forecast for 2016; it shows Clinton has a 72.6 percent chance of winning, as of writing. I say "as of writing" because it is updated as new state polls come in. If those polls show Trump suddenly going up in Florida, for example, that's likely going to cause Clinton's overall chances of winning the electoral college to dip. (Which they did today, because that's what happened in Florida.)

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What that 72.6 percent means, though, is not that Clinton is going to win because she is over 50 percent. It means that in the simulations that FiveThirtyEight has run, incorporating the odds offered by polls and demographic data in each of the states, Clinton ends up winning in 72.6 percent of those simulations. In more than a quarter of those simulations, Trump wins the presidency. So FiveThirtyEight's system says Clinton is more likely to win than Trump at this point. (Part of why Silver became famous in 2012 is that some prominent pollsters assumed the electorate would be friendlier to Romney, and they therefore showed him doing better. Silver, tracking the polls more broadly, ended up closer to the mark.)

We can also look at the RealClearPolitics polling average to see how predictive it has been. We created a tool that updates every day to convey this information. Plotted relative to Election Day, it looks like this:

It's messy. But what you want to look for is how much of each line dips underneath the zero point. Whenever a colored line is above the solid-black line, the person who won (or who is currently winning) was leading in the polling average. When the colored line dips below zero, he or she was trailing.

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As you can see, most of the time, the person who ended up winning was winning in the polling average.

This isn't proof, either. In 2004, George W. Bush — the red line — trailed John Kerry regularly (including in July). In 2012, Obama trailed Romney shortly before Election Day. Both ended up winning.

These polling averages can be subject to sudden spikes. In 2008, there were two moments when John McCain passed Barack Obama in the polls: when he solidified the Republican nomination and after his party's convention. If you looked at just the photo of just that moment, you may have thought McCain would win.

This suggests that we might see a similar burst for Trump coming up here shortly, given that the Republican convention is next week. Does this mean he's suddenly more likely to win? Not necessarily.