Smerconish: As next debate looms, time for Trump to hit the books

'I've got the Big Mo!" George H.W. Bush famously said after winning the Iowa caucus in 1980. Unfortunately for Bush, he soon lost the "I paid for this microphone!" debate with Ronald Reagan in New Hampshire that propelled the Gipper's turnaround toward capturing the Republican nomination.

Political campaigns are like that. Momentum can sometimes turn on a dime. Just ask Donald Trump.

Trump certainly had the Big Mo going into the first debate. The summer was a seesaw between Trump and Hillary Clinton, who benefited from a well-staged convention and the fact that it followed the GOP confab. The seemingly spontaneous speech by Khizr Khan, father of a fallen 27-year-old U.S. soldier in Iraq, was the apex of Clinton's ascendance.

After losing his postconvention focus, Trump made his second change in campaign management. Having initially dispatched Corey Lewandowski in favor of Paul Manafort, he then hired Kellyanne Conway to manage and installed Steve Bannon as his campaign chair. And somewhere in the background, Roger Ailes, suddenly with time on his hands, was reportedly lending his counsel. The short-term results were positive. Trump exhibited discipline; he stayed on message, avoided unscripted remarks, and wasn't exposed to endless interviews that run the risk of off-the-cuff errors. As the email controversy simmered and Clinton's health faltered, her margin vanished, just in time for their first face-to-face confrontation.

So Clinton was at a distinct disadvantage going into the first debate. She lacks the trust of a majority of the American public, and is running short on time to alter that perception. Trump's priority should have been a continuation of the control that Conway and Bannon had instilled. Instead, he fell prey to Clinton's efforts to show him as unhinged and unprepared.

In her second debate response, Clinton said his economic proposal represented "Trumped-up trickle-down." The line fell flat, but it was a sign that she was seeking to goad him. Then she said he had "started his business with $14 million, borrowed from his father." Trump initially refused to take the bait, and even attempted to show her deference by referring to her as "Secretary." ("Now, in all fairness to Secretary Clinton - yes, is that OK? Good. I want you to be very happy. It's very important to me.") But Clinton had a plan and she was having none of it. At her next available opportunity, she said: "In fact, Donald was one of the people who rooted for the housing crisis."

That was all it took. Trump disintegrated, lost focus, and missed several golden opportunities to accentuate her negatives. For example, after finally putting her emails in play, he surrendered an opportunity to prosecute that case and instead returned to a weak defense of his failure to release his tax returns. ("When you have your staff taking the Fifth Amendment, taking the Fifth so they're not prosecuted, when you have the man that set up the illegal server taking the Fifth, I think it's disgraceful. And believe me, this country thinks it's - really thinks it's disgraceful, also. As far as my tax returns . . .")

Now the question is, can he do anything to regain the Big Mo, or is the debate loss a tipping point for his descent in the final weeks of the campaign?

We won't know for sure until they face each other again at Washington University on Oct. 9 in a town-hall format featuring questions from both the moderators and a live audience of undecided voters. Trump's whining about moderator bias, his microphone, and online-poll results have not altered the perception that he lost. But keep in mind that Ronald Reagan bounced back from a poor first debate in 1984, and Barack Obama did likewise in 2012. Unfortunately for Trump, many more are voting early today than have done in the past, and so every day matters.

To state the obvious, the man needs to practice. Published reports say staffers could not get his attention when seeking to stage mock debates. Meanwhile, Clinton relished in her preparedness. ("I think Donald just criticized me for preparing for this debate. And, yes, I did. And you know what else I prepared for? I prepared to be president. And I think that's a good thing.") Her biggest triumph at Hofstra came in the way she managed the split screen that showed the two candidates at the same time. That comes from practice.

No amount of rehearsal will save Trump if he doesn't appreciate his audience. Primary and caucus season is over. This is no longer an exercise to fire up the GOP base. He's not preaching to a crowd eager to chant: "Lock her up." Instead, it's Trump's last chance to grow the tent, and he offered absolutely nothing in the first debate to move that needle.

The forces that brought Trump this far now impede his growth. If he doesn't realize that, the race is over.

Michael Smerconish can be heard from 9 a.m. to noon on SiriusXM's POTUS Channel 124 and seen hosting "Smerconish" at 9 a.m. Saturdays on CNN.