SCOTTSDALE, Ariz. — Three years from the next presidential election and long before the Republican primary field can take shape, the race for the GOP nomination already feels crowded.

As 26 of 30 Republican governors recently gathered here for their annual conference, no fewer than five were already being talked about as potential contenders in the 2016 presidential primary. It made for awkward moments as the would-be candidates jockeyed for position among their peers while simultaneously shying away from acknowledging the race.

Here was New Jersey Gov. Chris Christie, fresh off of his historic re-election victory in November, taking the reins of the hosting group, the Republican Governors Association. Gov. Rick Perry, of Texas, and Gov. John Kasich, of Ohio, sat on opposite ends of a panel discussion, and both later schmoozed with reporters. There was Gov. Bobby Jindal, of Louisiana, leading a news conference on the first day. And Wisconsin Gov. Scott Walker, in absentia during his East Coast book tour, trumpeted the GOP message from TV screens.

Republicans have been talking openly of their desire to have a governor as their nominee in 2016, someone with executive experience who knows what it's like to deal with a legislature. That buzz is greatly encouraging all of the governors, while the sheer number of chief executives from which to chose is exciting those who want to make one of them president.

But the concentrated dose of potential GOP presidential nominees laid bare the underlying question of what kind of governor the Republican Party will accept as its standard-bearer -- one who agreed to expand Medicaid in his state as codified under Obamacare, or one who refused to expand Medicaid and railed against the law.

All of the Republican governors are quick to profess a disdain for Obamacare overall. But, when the Supreme Court ruled last year that states could accept or reject the law's expansion of Medicaid funding, it created a divide among Republican governors as some accepted the money and others did not. Now, the issue will likely be held up as an ideological litmus test for any GOP governor running for the White House.

Some Republican chief executives, particularly those from traditionally blue states, argued that expanding Medicaid and creating insurance exchanges from which others could buy policies was in the best interest of their state. Others have taken a more ideological stand by turning down billions in additional federal funding to expand Medicaid and by refusing to create insurance exchanges.

Conservative Republicans are already portraying governors who accepted the money to expand Medicaid as Obamacare supporters. Sen. Rand Paul, R-Ky., another 2016 prospect, recently used the issue to beat up on Christie.

“In the case of the New Jersey governor, I think embracing Obamacare, expanding Medicaid in his state is very expensive and not fiscally conservative," Paul told CNN. “Many Republican governors, I would say, are conservative [and] did resist expanding and accepting Obamacare in their states."

One of the governors who refused to expand Medicaid, South Carolina Gov. Nikki Haley, sat next to Christie at a press conference when she was asked how voters in her early primary state would weigh the issue.

“I think it’s going to be an issue, certainly, that is talked about, just like others,” Haley finally said after circumventing a direct response. “But it won’t be the sole issue.”

The emerging awkwardness of Republican governors on the subject suggests the issue will indeed persist, and that those potential 2016 contenders who now dance politely around it will be forced to represent their stance to primary voters.

Kasich, of Ohio, is prepared to do just that. "I've looked at all the reasons to be against it, and it was really pretty simple for me," the Ohio governor said of his decision to expand Medicaid. "It was never a question ... I have a decision to make: $14 billion or no?"

New Mexico Gov. Susana Martinez, who's been talked about as a vice presidential contender, told the Washington Examiner that she expanded Medicaid in her state because “the decision was best for New Mexicans.”

“As governor, you have an absolute responsibility to do what’s best for the people in your state, not the people in your party, because that is who you represent, the people in your state,” Martinez said.

Martinez said she doesn't consider whether this stance will leave her vulnerable to conservative skewering — but most governors who have expanded Medicaid recognize that it will.

Perry, a 2012 presidential contender who may run against in 2016, debuted at the RGA conference a template for such criticism from the right.

“It’s like putting 1,000 more people on the Titanic when you knew what was going to happen,” he said of expanding Medicaid.