You can feel it — Republican confidence in victory is growing. Many in the GOP, from elected officials to pundits on the social platform X, believe former President Donald Trump is headed to victory, perhaps even a big victory, on Nov. 5. For weeks, Vice President Kamala Harris’ lead in national polls has been shrinking, a little bit each day, until now the two are basically tied, which some experts believe will mean a Trump win. Of the five most recent polls in the RealClearPolitics average of polls, one has Harris leading by a single point, another has Trump leading by a single point, and three have the two candidates exactly tied. You can’t get closer than that.

If you are a Trump supporter, it appears the national polls are lining up. The same with the swing state polls. Early voting looks better for Republicans than it ever has. Trump is running a smart race. Harris has failed to offer a compelling picture of what she would do were she elected president of the United States. So the Republican optimists are not making this up.

At the same time, the polls are really, really close. Why such a high level of confidence? The reason is that recent experience suggests the Democratic candidate has to win the popular vote by a certain margin — say, 3 percentage points — in order to win the Electoral College. They can win by, say, 5 million votes in California, which juices up the national popular vote, but they’ll take home the same 54 electoral votes they would have captured if they won the state by, say, 5,000 votes.

Hillary Clinton won the popular vote by 2.1 percentage points in 2016 — and lost in the Electoral College. Joe Biden won the popular vote by 4.5 points in 2020 — and won. Now, although it’s hard to pinpoint a precise figure, Harris probably needs to win the popular vote by some margin, a point or 2, or maybe 3, to win the Electoral College, and thus the presidency.

That’s what makes the current Harris-Trump popular vote polling tie so encouraging to Trump supporters. They have a pretty simple view of it: If we tie, we win.

Trump supporters also know that many polls in 2016 and 2020 undercounted Trump voters. When the final election results came in, Trump outperformed the polls. So some Trump people look at today’s polls and say, OK, add 2 points, and that’s what Trump will get. Thus, if the polls say the race is tied, they think they’re really 2 points ahead.

But there’s another thing to consider. Pollsters are well aware that they did a poor job in 2016. They tried to fix things in 2020 and did not succeed. Now, they have tried new methods to make their 2024 polls more accurate. The question is whether they have succeeded this time. If they have, the race is really tied. If they haven’t, you can add a couple of points to Trump’s total.

Finally, there is the margin of error. The polls never claim to be right on the money. And the Harris-Trump margin has always been within the margin of error of each individual poll. If, in fact, they are wrong, will they all be wrong in the same direction, as they mostly were in the past? Not clear.

So here’s the thing: Yes, the polls have shown real movement toward Trump in the last few weeks. Yes, there are certain factors favoring Trump. But the polls are not frozen at this moment. There are still several days left in the campaign for people to vote.

The polls could shift a bit. They could move back toward Harris. And we know Democrats, whatever they think of Harris, hate Trump with a passion, which will motivate them to vote. Plus, if the pollsters have fixed some of their Trump undercount problem, the final result could be very, very close — certainly not a good reason for Republicans to be highly confident today.

You know the phrase “irrational exuberance”? For Trump supporters, the situation is somewhere between rational and irrational exuberance. Yes, optimism makes sense given where things are at this very moment. But it would be foolish to start assuming that the next week will be a smooth ride toward a Trump victory. Something that you don’t expect can always happen.

Byron York is chief political correspondent for The Washington Examiner.