M. Spencer Green / AP Iowa Governor Terry Branstad speaks in Chicago on Aug. 9, 2013

If you want to see the battle for the future of the Republican Party, look no further than the first state on the 2016 nominating calendar.

Iowa has become a proving ground for the Republican Party’s various ideological wings. As Chris Christie and Rand Paul duke it out on foreign policy, Marco Rubio and Ted Cruz battle over immigration reform. It’s the struggle in the state that will in many ways shape the future of the GOP. Indeed, the fight for the heart and soul of the Republican Party in Iowa is in many ways a proxy for the national party’s struggle for its identity.

In particular, the state has become a test case for how the Republican Party incorporates a growing libertarian contingent. In 2012, supporters of then Representative Ron Paul took over the state party — and altered the results of the Iowa caucuses — by out-organizing the rest of the Republican field at the state convention. What followed was more than a year of recriminations and feuds and fundraising challenges.

“It’s fair to say there is more tension within the party than I’ve seen in many, many years,” says the state’s Republican national committeeman Steve Scheffler. “And I think we’ve seen that on the national level too.”

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The GOP in Iowa is roughly equally divided among the GOP’s warring factions — the Establishment, the social conservatives and the libertarians. Combine two of the three and you have an ironclad grip on the party. That’s exactly what happened in 2012, when evangelicals threw their support behind the so-called Liberty movement of Paul supporters, with chairman A.J. Spiker repeatedly clashing with longtime Establishment governor Terry Branstad. The challenge for Republicans is that with Democratic gains among youth voters and Hispanics, they need all three factions to get along.

“The Establishment needs to find a way to work with them,” Scheffler says. “The new people need to understand there is a process and you have to work within the process. Otherwise we’re in deep trouble.”

“Iowa will decide whether we can keep our eye on the ball, or if we’ll shoot our nominee in the foot like in 2012,” said one RNC member last weekend.

Republicans are far from the first to view Iowa as a test tube for national trends. In 2012, President Barack Obama’s campaign looked to Iowa as a touchstone — in part owing to the swing electorate and in part to the emotional connection to the state that started Obama on the path to the White House. In his book, Collision 2012: Obama vs. Romney and the Future of Elections in America, Dan Balz wrote that the Obama team sent researchers to focus-group the bellwether state after Obama’s “shellacking” in the 2010 midterm. Republicans see the same role for Iowa in the coming months and years.

“There is a large segment of the Republican Party that wants us to stand up and show some bold leadership on these things,” says Spiker. “The other side says we can’t or we’ll lose. I say if we can’t take stands, why were we sent here?”

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According to several longtime Republican operatives in the state, Branstad is building a substantial field team outside of the state party for his re-election next year — designed in part to retake precinct and county leadership posts lost by the Establishment last year. “Our sole priority is to build a grassroots organization for Governor Branstad and Lieut. Governor [Kim] Reynolds,” says Branstad spokesman Jimmy Centers. Retaking control of the state convention would ensure a smooth renomination for the pair. But the broader motivations are also clear — an attempt to check the power of the Liberty movement in advance of the 2016 caucuses.

“When you have a group that has controlled the party for 50 years, they’re not going to go away quietly. They want control again,” Spiker says.

“The GOP in Iowa is likely headed for a showdown between people who care more about the R behind the candidate’s name and the party’s values writ large and those who are driving the ‘Big Liberty’ bus but haven’t toiled in the fields of the party except to help one candidate,” says Iowa Republican consultant and former Romney aide Dave Kochel.

“It’s important to put forward the most wide-reaching coalition of activists if we’re going to engage enough voters to win elections,” Kochel adds. “The success candidates like Chuck Grassley and Terry Branstad have had in Iowa has long depended on a far bigger coalition than is currently represented by our state party or interest groups like we see in these early forums.”

As 2016 approaches, Branstad sees the divisions in Iowa as an appropriate battlefield for the future of the national party. “Everyone is welcome, and we encourage them all to come and share their ideas with Iowans, and let Iowans make a judgment of who they think is the strongest and the best,” says Branstad, striking a diplomatic note.

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