This article is from the archive of our partner National Journal

Nearly all of the GOP's top presidential prospects will flock to the Iowa State Fairgrounds in March at the request of one man: Bruce Rastetter.

Outside of Iowa, Rastetter is virtually unknown. But in the state, he is a major Republican power player whose own sway—combined with Iowa's influence in the race for the GOP nomination—is enough to convinces comers from all corners of the party to heed his call.

And so, the guest list for Rastetter's "Iowa Agriculture Summit" is a who's-who of contenders for 2016: As of Thursday, the list includes Jeb Bush, Chris Christie, Ted Cruz, Mike Huckabee, Scott Walker, Rick Perry, Rick Santorum and George Pataki. Marco Rubio's camp says he hopes to attend the summit, but he has a wedding in the family scheduled the same day.

"Any event that is hosted by someone of Bruce's stature that also has the blessing of Iowa's Republican leadership is something most candidates are not going to want to miss," former Iowa Republican Party chairman Matt Strawn said.

Part of the summit's appeal for candidates is the chance to address Iowa voters, the same ones who will control the candidates' fates in the 2016 Iowa caucus. But the candidates also are there seeking an audience with Rastetter, hoping to score the support of a mega-donor with deep pockets and deep ties in Iowa—and whose support in still up for grabs.

"I think he's one of the few individuals in the state that could put together an event like this and draw a diverse crowd of people," said Craig Robinson, a former political director for the Iowa Republican Party who now edits the Iowa Republican.

Rastetter has a track record of success. He was instrumental in convincing Terry Branstad to run for governor again in 2010, and was one of his largest contributors during that campaign and in 2014. (Branstad—along with Iowa Rep. Steve King and Sen. Chuck Grassley—are slated to attend the March agriculture summit.) Rastetter, who took over as president of the Iowa Board of Regents in 2013, was an early supporter of Joni Ernst's successful 2014 Senate bid. And at a national level, he provided the seed money for American Future Fund, which has been one of the top-spending outside groups in recent election cycles, when the nonprofit group formed in 2008.

Now, Rastetter has invited every Republican who is considering a White House bid to Des Moines on March 7 in hopes of spurring a "substantive discussion" on topics such as renewable fuels, biotechnology, conservation and sustainability—issues Rastetter and other members of the agriculture industry say have been pushed to the back burner in past presidential campaigns, despite their importance to the state's economy.

Each of the White House aspirants that attends the summit will have 20 minutes on stage to deliver brief opening remarks, then field questions from Rastetter himself.

"I think this event is him kind of stepping out and using his influence in a different capacity than he's done before. This is a really different type of political event than we've ever seen in this state," Robinson said. "I think this makes him much more of a player in this Iowa caucus race than it did in any previous presidential campaign."

It remains unclear which candidate Rastetter will back, and he's keeping coy about where he stands on the issues that the candidates are coming to Iowa to discuss. He said he supports "modern, sustainable, environmentally-sound agriculture," but he declined to elaborate where he stands on some of the specific issues he will ask the summit's attendees to address. "It's about where the candidates come out on the positions, not my positions," Rastetter said.

While Rastetter did not hold an event like this during the previous presidential cycle, he tried to impact the result in a different way. Rastetter and six other Iowa Republican financiers flew to New Jersey in May 2011 to try to convince Christie to run for the GOP nomination. When Christie opted not to enter the race, Rastetter did not publicly back a candidate, even though his support was heavily courted.

This time around, Rastetter isn't getting behind the New Jersey governor as he explores a White House bid—at least not yet. Rastetter said that "at some point in time" he will endorse a presidential candidate, adding that the summit will begin to help him make that decision.

"I think Chris Christie is going to be one of the contenders in the presidential race. I've told him, as I've told others, that I have not picked a candidate and I won't for some time," Rastetter said. "And I think it's important here in particular that I just be a fair arbitrator of the questions that are asked to all of them."

While Republicans dominate the slate of speakers for the event at the moment, Rastetter still wants to make the summit a bipartisan one. He's invited Hillary Clinton, Joe Biden, former Maryland Gov. Martin O'Malley, former Sen. Jim Webb of Virginia, Sen. Bernie Sanders of Vermont and others to attend as well. Branstad met briefly with Biden on Thursday during the vice president's trip to the state and encouraged him to attend the summit, according to the governor's spokesman.

Asked if the fact that many of the organizers are the summit are Republican would deter Democrats from attending, Rastetter said, "I'm sure that's a consideration. But the issues aren't partisan."

The summit won't be Rastetter's first interaction with many of the Republicans considering a White House run. Rastetter is famous for holding an annual summer party at his central Iowa home and typically invites powerful figures from the political and business worlds to attend. Cruz and Rubio both made appearances last year, while Louisiana Gov. Bobby Jindal flew to Iowa for the event in 2013.

Rastetter said he anticipates that much of the 2016 GOP field will receive invitations to this year's get-together. But by then, they'll have already been courting Rastetter for months.

This article is from the archive of our partner National Journal.

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