Republican presidential nominee Donald Trump, left, and Democratic presidential nominee...

Republican presidential nominee Donald Trump, left, and Democratic presidential nominee Hillary Clinton speak during the second presidential debate at Washington University in St. Louis, Sunday, Oct. 9, 2016. Credit: AP

Less than two weeks before Election Day, we are seeing a race within the presidential race — a struggle between the major-party candidates just to look like they’re about to win.

Most mainstream polls as of now give Hillary Clinton an edge. One survey from the past few days put her in the lead by 12 points nationwide, another by 5 points.

Donald Trump calls these polls fake — and instead chooses to tout other, “outlier” polls that show him tied or slightly ahead, even as his campaign manager, Kellyanne Conway, says: “We are behind. She has some advantages.”

On Sunday, Clinton campaign manager Robby Mook called it “eye-popping” that in some states the vote-by-mail applications suggested more Democrats than Republicans are casting early ballots.

Nobody really knows how it will break — which leads to the question of why a candidate would insist so heatedly that she or he is ahead before ballots are counted.

Candidates have several reasons for trying to keep up appearances as they do.

One is money. Funds are raised until the late hours of the campaign, and candidates who seem to be fading or behind may strike donors as bad political investments.

Another reason is terrain. The Clinton camp would like to see Trump put resources and efforts into shoring up states that would ordinarily go Republican but threaten to be contested.

Morale provides another incentive to look like the favorite.

One longtime operative said: “Polls direct money, momentum and enthusiasm. You can see a perceptible change in excitement in a campaign where polls have a candidate up versus down. It’s not critical or defining, but helpful in the final weeks.”

And then there is the unknown factor of how voters will act in light of who they believe is winning.

Trump on Monday raged against news media and the conventionally gathered polls they have published. “It’s called voter suppression, because people will say, ‘Aw, gee, Trump’s out.’ ”

In other words, discouragement breeds bad turnout.

Trump is also hurling back the Democrats’ charge that he is trying to suppress votes by pre-emptively claiming a fix and demanding the involvement of poll-watching teams.

But candidates generally have cause to worry that if polls show them trailing, their voters will be less than sure to show up. If polls show the contestants close, it might convince voters to believe they can make a difference.

Personalities matter, too. Perhaps more than any other candidate, Trump boasts of winning. His is a persona that seems especially unwilling to admit defeat.

Prematurely, as if bracing himself, he has called the election “rigged.” Just as prematurely, as if to jostle Trump, Clinton calls him a “sore loser.”

Only the vote will resolve this perception game for real.

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