The conservative groups that supported Michigan’s new “right to work” law — winning a stunning victory over unions, even in the heart of American labor — vowed Wednesday to replicate that success elsewhere.

But the search for the next Michigan could be difficult.

National unions, caught flat-footed in the Wolverine State, pledged to offer fierce opposition wherever the idea crops up next. They consider the laws a direct attack on their finances and political clout at a time when labor influence is already greatly diminished.

In addition, few Republican governors who could enact such legislation seem eager to bring the fight to their states.

“There is not much of a movement to do it,” Pennsylvania Gov. Tom Corbett told a Philadelphia radio station this week, according to the Associated Press. His lack of enthusiasm was shared by two other governors who have battled with unions, Wisconsin’s Scott Walker and Ohio’s John Kasich.

States that have enacted right-to-work laws. (The Washington Post/-)

Right-to-work measures like the one Michigan Gov. Rick Snyder (R) signed Tuesday allow workers to opt out of paying union dues. Advocates say the laws, now in force in 24 states, offer employees greater freedom and make states more competitive in attracting jobs.

“If Michigan can do it, then I think everybody ought to think about it,” said Mark Mix, president of the National Right to Work Legal Defense Foundation. He said he thinks at least one more state will adopt such a law before the end of 2013, and listed Alaska, Missouri, Montana and Pennsylvania among the top contenders. “Very confident. It will happen. [But] I can’t tell you where the next one is.”

The boisterous protesters who had stormed Michigan’s State Capitol in Lansing on Tuesday were gone on Wednesday, dispersed after Snyder signed the legislation.

Only about 30 demonstrators stood in front of the building on Wednesday, their mouths covered in duct tape that said, “$1,500 Less.” The figure represents the difference in the average annual salary of workers in right-to-work states compared with states without such laws, protest organizers said.

Andy Schor, a Democratic state representative-elect, said the push for the right-to-work measure was part of “a national effort” by outside conservative groups to undercut union power. “We’re the next domino to fall here in Michigan,” he said.

Opponents of the law said they are considering their options, including a possible legal challenge and stepped-up campaigning against Snyder, who will face reelection in 2014.

In a telephone interview, Snyder — who had repeatedly said he would not sign a right-to-work measure — sought to explain how he had changed his mind. The first-term governor, elected during the GOP wave of 2010, said he had been encouraged by the example of Indiana, which passed a right-to-work bill this year.

But Snyder said Michigan’s labor movement was partly to blame for pursuing a ballot measure this year that would have added protections for collective bargaining. It failed, helping spur the push for the legislation signed Tuesday.

“ ‘You’re opening up the whole realm of labor issues, including right-to-work, so I would expect to see a big push for right-to-work. So please, don’t go ahead,’ ” Snyder said he told labor groups, adding: “They ignored that advice.”

Labor expert Richard Hurd of Cornell University estimated that unions in Michigan might expect to lose 20 percent to 30 percent of their revenue, although precise figures are difficult to gauge. Before Indiana, the last state to make the change to a right-to-work system was Oklahoma in 2001.

In the 26 states without such legislation, conservatives have a renewed sense of hope. “I support this goal on the national and state level and look forward to Kentucky joining Michigan in the near future,” Sen. Rand Paul (R-Ky.) said in a statement.

Even in blue New Jersey, a major backer of right-to-work bills said the shift this week in Lansing had changed some minds.

“I think that what happened in Michigan sent a signal that people in states with histories of strong unions are now open to a new perspective,” said state Assemblywoman Amy H. Handlin (R).

On the other hand, national labor officials said Wednesday that they are confident that no other states will follow Michigan’s lead in the near future.

“In terms of bigger, bluer, more-union states, we’re not worried that this is going to lead to a new anti-union push in those states,” said Eddie Vale, spokesman for Workers’ Voice, a super PAC associated with the AFL-CIO. “There still will be state battles, but I think that we’re getting to the end of the 2010 tea-party wave rather than a resurgence of them.”

On Wednesday, a survey of state leaders found that a law like Michigan’s would still face significant obstacles in many places.

In some cases, the roadblock is a Democratic governor. Conservatives have hopes for a right-to-work law in Montana, but Gov.-elect Steve Bullock (D) said he would oppose one: “I don’t think that’s what we need to build our economy.”

The situation is similar in New Hampshire. “I would veto it if it came to my desk,” Gov.-elect Maggie Hassan (D) said in a telephone interview on Wednesday. In both Kentucky and Missouri, Democratic governors also have spoken against such laws.

In Maine, Paul LePage (R) has said that he supports right-to-work legislation but is likely to run into opposition in the soon-to-be-Democratic state legislature.

Said state Rep. Tom Winsor (R), a longtime supporter of right-to-work legislation: “I’m not the brightest bulb, but I can count noses.”

Even GOP-controlled states were leery on Wednesday.

“If I could wave a magic wand, I would do it tomorrow. But in terms of trying to get it through our legislative process, it is a very heavy lift,” said David Patti, president of the Pennsylvania Business Council. Would a right-to-work bill pass there? “No,” Patti said flatly.

In Ohio, a state with a Republican governor and Republican legislature, citizen activists have reached the same conclusion. An effort is underway to go around the state’s politicians and put a right-to-work measure on the ballot next year.

“When we didn’t see any interest necessarily in the statehouse, we said, ‘Hey, we’re going to move forward,’ ” said Chris Littleton of the group Ohioans for Workplace Freedom. They need 386,000 signatures by next July.

How many do they have? “It’s safe to say we’re under 100,000,” he said.

Fahrenthold reported from Washington.