Republican presidential nominee Donald Trump (Drew Angerer/Bloomberg News)

Donald Trump and polls have had a long and unusually good relationship. Throughout the Republican primary, polls showed Trump at or near the top of the field. He dutifully cited them — and cited them — as evidence that he was #winning, and that everyone who second-guessed his unorthodox campaign style was, in a word, dumb.

It was Trump's ultimate defense. Every time another candidate or a party leader raised questions about his fitness for office or his conservative credentials, he could always point to polling that showed the Republican primary electorate siding with him. It served as his uber-example of how out of touch the party establishment was with its base; every time they predicted something he said or did would doom his campaign, his poll numbers went up. (See Muslim ban, build wall and make Mexico pay for it, etc.)

Of late, though, the Trump-polls friendship has fallen on hard times. Very hard times.

He's down 17 points to Hillary Clinton in New Hampshire. Down 11 in Pennsylvania. Down six in Michigan. And national polling is no better. A Fox News survey out Wednesday night had Trump down 10 to Clinton. That's consistent with the post-conventions landscape in lots of polls released over the past five days.

That polling reality doesn't mean that Trump isn't still trying to lean on polls to make the point that he is winning. At the start of a rally Wednesday in Daytona Beach, Fla., Trump cited a "new" poll that showed him ahead by eight points in Florida. But there hasn't been any "new" polling done since early July — before the two conventions —in the state. And, of the 14 most recent polls in the state, Trump has led Clinton in just four.

For the past 15 months, we've all been wondering what would happen to Trump if his beloved poll numbers took a turn for the worst. So much of Trump's pitch to voters was based on his standing in the polls — I'm winning and that means I am a winner and, therefore, someone you should vote for — that it was hard to imagine what he would even say if he wasn't ahead.

That question never really got answered in the primary because Trump never experienced any sort of extended polling slump. But it is quite clearly happening right now.

Trump seems to be struggling to deal with it. In Jacksonville on Wednesday night, Trump went through his usual litany of the big crowds he is drawing — "We go to Oklahoma, we had 25,000 people. We had 21,000 people in Dallas" — before turning more introspective: “I hear we’re leading Florida by a bit,” he said. “I don’t know why we’re not leading by a lot. Maybe crowds don’t make the difference.”

The smartest thing Trump could do when asked about his poll problems is to note that Clinton is enjoying a very traditional convention bounce and that the race will eventually settle down to a close single digit contest.

But Trump rarely does the politically smart thing — particularly when he feels betrayed by the same polls that were so good to him for so long. And there are already indications that Trump — a friend spurned — is going to burn the bridges of his past close relationship with polls.

"I think these polls — I don't know — there's something about these polls, there's something phony," Trump said Tuesday at a rally in Loudoun County, Va.