(ABC News)

Of all the names on the 2016 GOP presidential shortlist, only Wisconsin Gov. Scott Walker must win a tough re-election fight in his home state before setting his sights on the White House.

Even as Walker fights backlash from new revelations surrounding allegations of illegal campaign coordination, his path to the White House raises a new question: Will the talk of 2016 hurt his re-election chances this November?

Walker became a national Republican star after eliminating collective bargaining for public unions in 2011 and weathering a recall attempt in 2012 - an impressive feat in a state that has sided with Democrats in the last seven presidential contests.

"There's obviously a lot of support for Walker around here," said Charlie Sykes, a conservative radio host in Milwaukee. "But there's also simmering concern that the buzz might be a distraction in what's going to be a tough re-election fight."

Walker has said his focus remains on 2014, but told ABC News in November he would not commit to serving out a full second term as governor.

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He also doesn't shy away from discussing national politics. In 2012, he sent a letter to Mitt Romney with suggestions for his presidential campaign. (Romney never responded.)

"When you start hearing him talking about foreign policy or Hillary Clinton, there is that concern," Sykes said, commenting on remarks Walker made recently at a New Jersey fundraiser that were recounted in the National Review.

There are also the out-of-state trips. Walker has visited Republicans in Iowa and attended fundraisers with deep-pocketed donors in New York and Texas.

To Sen. Ron Johnson, R-Wis., who said the presidential speculation could help Walker "raise his profile," Walker's out-of-state fundraising is nothing to hold against him.

"Unfortunately, politics is getting pretty expensive," Johnson said.

In the governor's race, Walker's Democratic challenger, former state Commerce Secretary Mary Burke, has never been elected to statewide office. But a recent poll from Marquette University Law School shows the two in a dead heat.

The polling "doesn't mean he's not the favorite, but it doesn't mean he can take his election for granted," said Craig Gilbert, the Washington bureau chief for the Milwaukee Journal-Sentinel, who has written extensively about Wisconsin's polarized electorate and Walker's path to the presidency.

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The poll also found that just 27 percent of respondents want Walker to run for president in 2016, and that 31 percent believe a governor could run for president and "still handle their duties as governor."

More crucial for Walker's re-election prospects, according to the Marquette University Law School pollster Charles Franklin, are the responses to questions about perceptions of Walker and Wisconsin's economy, which both parties have called the most important issue of the upcoming election.

According to the poll, roughly 53 percent of voters believe Wisconsin is "going in the right direction," while 44 percent believe Walker "cares about people like me."

Tying perception of a sluggish economy to Walker's national profile and presidential ambitions could be "poison" for the governor in November, said Franklin.

"This would be something that the Burke campaign would have to develop into an issue … that the state is not doing as great as he said, and he's not in it for the voters of Wisconsin," he added.

The Walker campaign did not respond to ABC News' requests for comment.

But long before he contends with his presidential aspirations, Walker has more pressing challenges.

On Thursday, a federal appeals judge unsealed court documents that allege a "criminal scheme" between Walker and advisers to bypass federal election laws meant to prevent illegal campaign coordination.

The documents detail the prosecutors' argument, and reference an email Walker sent to Republican strategist Karl Rove about the workings of the Wisconsin Club for Growth, a conservative group managed by longtime Walker adviser R.J. Johnson.

State prosecutors have been investigating Walker's 2011 recall campaign for illegal coordination in what is known as a John Doe probe in Wisconsin, a secret investigation supervised by a judge.

Last month, a judge ruled to stop the investigation, which was appealed and brought before an appeals court. The federal judge reviewing the lawsuit released the documents Thursday.

Walker wasted little time in responding, appearing this morning on Fox and Friends to call the claims "politically motivated."

He also published an editorial in the Milwaukee Journal-Sentinel on the topic. It's title: "I will not back down."