Republicans scored a big victory in Wisconsin Tuesday, but Gov. Scott Walker says there is "no doubt" Mitt Romney is still the underdog in his state when it comes to the presidential election.

"I mean the president having grown up just across the way in Chicago gives him a certain advantage, at least geographically," Walker said in interview with ABC News.  "But I still think we are a very competitive state."

Walker also has some advice for Romney:  Lay out specific plans for how he would deal with the federal budget crisis and be honest with the tough choices that need to be made.

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"What it boils down to is can Governor Romney talk about a clear strategy to get the country moving forward to take on the tough economic and fiscal crisis this country faces?" Walker said.  "If he can lay that plan out clearly, I think voters in Wisconsin will at least give him a shot."

Even as he celebrates a big victory, Walker acknowledges that he would have handled his budget crisis differently if he had a chance to do it all over again.  For starters, he said, he would have explained to the public what he was going to do before doing it.

"My problem was I was so eager to fix it I didn't talk about it. I just fixed it," Walker said.   "Most politicians talk about it but never fix it in the future. We have learned from this. We are going to both talk about, get people engaged, work on solutions together and then fix it."

He says Romney should not make the same mistake.

"In Governor  Romney's case, I think the country is hungry," he said. "You look at the responses to [Rep.] Paul Ryan's [budget] plan; I think the country is hungry for leaders who are willing  to stand up and say it like it is and tell people what they are going to do and then mean it and … I think if the governor can really lay that out crystal clear to voters here in Wisconsin and across the  country, I think he can be competitive. "

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