AMES, Iowa -- In September, when Donald Trump appeared before a giant rally in Dallas, a person in the Trump circle described the coming months of the campaign. Sure, a big event like Dallas got headlines, but Trump knew he couldn't do the same rally, rally, rally for the next several months and expect the public to remain interested. Even then, TrumpWorld was planning a varied (and secret) schedule of special events, bold policy rollouts, and other attention-getting gestures to keep the voters' and the media's attention over the course of a long campaign.

Tuesday night in Ames was a prime example of Trump's timing and showmanship. Bringing Sarah Palin to Iowa grabbed all eyes in the Republican caucus race. And it seriously undercut the notion, growing in some political circles, that GOP rival Ted Cruz has nailed down the support of all of Iowa's conservatives.

Palin, whose last highly-publicized visit to Iowa was a poorly-received speech at Rep. Steve King's candidate summit in January 2015, was her most Palinesque self. Discussing who is and who is not a conservative, for example, she said, "How about the rest of us? Right-winging bitter clinging, proud clingers of our guns, our God, our religions, and our Constitution…" At other times, her style was her own brand of lyricism: "We all have a part in this, we all have a responsibility, looking around at all of you, you hard-working Iowa families, you farm families and teachers and Teamsters and cops and cooks, you rock 'n' rollers and holy rollers, all of you who work so hard, you full-time moms, you with the hands that rock the cradle, you all make the world go 'round, and now our cause is one."

But Trump was happy to have Palin for more reasons than her ability to entertain a crowd. Even though she is much diminished from her heyday a few years ago, Palin still has influence among some conservatives. Trump now has that on his side, and just as important, Cruz doesn't.

At the rally I talked with Jamie Johnson, a veteran Iowa politico who supported Rick Santorum in 2012 and Rick Perry earlier in this race, but is now unaffiliated. Johnson saw the Palin move entirely in terms of persuading voters at the margins of the Trump vs. Cruz contest.

"I think the Palin endorsement is important for all of the Tea Partiers who were deciding which of the two they were going to vote for," Johnson said.

Does Palin still have clout in Iowa?

"To Tea Partiers, she does."

"How big a part of the electorate is that?"

"Probably 15 to 20 percent of the people who caucus. I'd say 15 to 20 percent would identify themselves as Tea Partiers more than anything else, such as born-again evangelicals."

"And you would expect that some of them are caught on the fence now between Trump and Cruz?"

"I know for a fact that they are," Johnson replied. "I've talked to several people in the last two months who have been on the fence between Trump and Cruz. So if they're on the fence, this might be just enough to push them over."

Indeed, at Trump and Cruz events in the last two weeks, I have met plenty of people who were for Trump, with Cruz as their second choice, or were for Cruz, with Trump as their second choice. For some of them, Palin's seal of approval might make some difference. Before she spoke, I asked several people at the Ames rally whether Palin had worn out her welcome; none thought she had.

"It's a valuable endorsement because people still view her as an anti-establishment outsider who they can also relate to," said Craig Robinson, a former Iowa state GOP political director who founded the Iowa Republican blog. "And if there is any strategy to the Trump campaign, it is to dominate the media coverage of the race, and Palin's endorsement will certainly help with that."

That's an understatement. Palin's appearance with Trump immediately captured nearly all the media's attention. In coming days, it will inspire impassioned debate, make talking heads explode, and cause fevered speculation across cable TV.

In Iowa, though, some in the Cruz camp were almost relieved to see Palin get so much attention, because it directed coverage away from a potentially far more serious problem for Cruz. Just a few hours before Palin appeared Tuesday, Iowa Republican Gov. Terry Branstad, a hugely influential figure in the state, publicly said he wants Cruz to lose in the caucuses. Branstad, a supporter of ethanol, made the statement at a renewable fuels conference; Cruz, of course, opposes the federal ethanol mandate. "[Cruz] hasn't supported renewable fuels, and I think it would be a big mistake for Iowa to support him," Branstad said.

That hurts.

In the early hours of Tuesday, before the Branstad and Palin developments, the Cruz camp felt things were going pretty well. They believed Cruz had gotten the upper hand in his feud with Trump over constitutional eligibility, "New York values," and other topics. CruzWorld pointed to talk radio hosts criticizing Trump as proof that Cruz had come out ahead. "Mark Levin just erupted at [Trump], and Rush did as well," a Cruz aide said Tuesday morning. "When they say 'cut the crap,' it has a pretty powerful effect." (In fact, Limbaugh's objection to Trump was a bit more nuanced than that, but Cruz still counted it as a victory.)

In a morning conversation, one Cruz aide expressed confidence that Cruz could counter any attack Trump threw at him. Cruz can fight as long as he needs to, the aide suggested: "It's going to stop when Trump wants it to stop."

That good feeling disappeared quickly as Tuesday went on. A few hours later, Iowans were talking about Branstad, and then everybody was talking about Palin.

And on Palin, one final, indirect effect of her endorsement is that the Cruz camp is left to wonder what Trump has coming up next. "He has to have another couple of tricks up his sleeve before the caucuses," said one Cruz supporter over drinks late Tuesday. The problem is that Team Cruz doesn't know what those tricks are. They'll find out when Trump wants them to.