President Trump insisted on the campaign trail he would get America winning again — so much so that, he claimed, people would ask that America stop winning, just so we could catch our breath. We never win anymore, he would complain, promising that a Trump administration would turn that losing record around.

One of the ways he would ensure he kept winning, it turns out, was simply by denying he was losing. Trump has an aversion to talking about bad news or acknowledging downsides and, in his turn-it-around-on-them style, will instead insist that his opponents are really the ones losing.

During the campaign, that took various forms, from his calling Hillary Clinton a puppet of the Russian government to his insistence that the polls were all wrong, that they underrecorded his support and that the only way he might lose key states was if voter fraud occurred. At least on that middle part, about the polls, he ended up being right in a microcosmic sense, and that validation seems to have defined much of his first 20 months in office.

As the midterm elections began to loom, polls suggested that Democrats were well positioned to make gains in the House, if not to take control of Congress entirely. Trump’s instincts kicked in: No, Democrats weren’t going to see a blue wave. Instead there would be a red wave of support for his party. No puppet; you’re the puppet.

He mentioned the red wave in campaign rallies. He mentioned it in tweets.

Whether he believes this is probably beside the point. What is important is showing that he and his party are winning, and that means saying you are going to win.

But, in this case at least, that is a problem. If you tell people you are going to beat the odds and the pollsters and win the presidency and you do, your supporters could be forgiven for believing your rhetoric about winning the House in 2018 as well. If they believe that, well, how important could it be to go out and vote if you are going to win anyway?

Trump stands at the center of the midterm elections, for better or worse. Democrats have proved to be highly motivated to get to the polls in primary elections, a sign of enthusiasm in the party. A CNN-SSRS poll released earlier this month found that 38 percent of Democrats say they are “extremely enthusiastic” about voting this year, compared with only 32 percent of Republicans. The result? The Democrats have a 16-point advantage on the generic ballot among those who are enthusiastic to vote and only a two-point advantage among those unenthusiastic about doing so.

This is important in part because the Republican base tends to vote more heavily in lower-turnout elections such as midterms. Voting reliability correlates to age, income and homeownership, all factors that tend to point to Republican voters. Democrats need a surge in enthusiasm in lower-turnout elections to make up for the Republicans' advantage in having a base that goes out to vote regularly regardless.

In a contest with amped-up Democrats, though, that should not be taken for granted. Republicans need good turnout, too — which Trump appears to be hampering.

Bloomberg News’s Joshua Green obtained an internal Republican Party poll showing Trump’s assertions of how well the party would do are having precisely the least-helpful effect on Republican voters: Disinclining them to care about voting.

Many voters "don’t believe there is anything at stake in this election,” the document reads in a section titled “Take-Aways.” "Put simply, they don’t believe that Democrats will win the House. (Why should they believe the same prognosticators who told them that Hillary Clinton was going to be elected president?)”

The short answer to that question (which is a constant response to midterm polling) is that national 2016 polling was on the mark. Most polls showed Clinton with a slight edge; on Election Day, she held a slight edge in the popular vote. It was several state polls, in places where Trump won narrowly, where the polls missed — meaning electoral college estimates missed and predictions of who would win followed suit. In congressional polling, there is no equivalent divide between the votes that are cast and the determination of a winner.

A graph included in Green’s report makes the point of the GOP’s poll clearly: Republicans are about as likely to say Democrats will regain control of the House as to say they will not. Strong Trump supporters are much more likely to say this will not happen. If they believe that, how urgently will they prioritize voting in November?

The poll indicates other problems for the party, including that it will need to encourage people with lukewarm feelings about the president, people who, for example, like his policies but not his mannerisms. Trump’s decision to spend a lot of time holding rallies before the midterms would seem likely to highlight the latter far more than the former.

None of this is to say Trump has not accounted for the possibility Republicans will do worse in November than he would like to admit.

At a rally in Montana earlier this month, he explained the only way in which he might face impeachment.

“If it does happen, it’s your fault, because you didn’t go out to vote. Okay? You didn’t go out to vote,” he said. “You didn’t go out to vote. That’s the only way it could happen.”

He is right that it is up to the voters to decide control of the House. But when what they consistently hear from the president they respect (and trust more than the media) is the Democrats do not stand a chance? Well, that message about how important it is to vote gets a bit muddy.