House GOP leaders’ embrace of a visa program for seasonal immigrant workers has come under fire from Members of their own party who want tougher enforcement measures put in place first and question the need for more imported labor during an economic downturn.

The party’s most ardent foes of illegal immigration say the party should oppose any expansion of immigration until the borders are secure and existing visas are enforced.

“There is a credibility gap for D.C. that has to be bridged first,” said Rep. Brian Bilbray (R-Calif.), chairman of the Immigration Reform Caucus. “We need to earn their trust by showing we’re moving on enforcement. That’s exactly why the American people are frustrated with this town. We’re not willing to do the heavy lifting first.”

Last week, Republican Conference Chairman Adam Putnam (Fla.) signed a discharge petition to bring Rep. Bart Stupak’s (D-Mich.) bill extending the H-2B visa program to the floor, and other GOP leaders, including Minority Leader John Boehner (Ohio) and Minority Whip Roy Blunt (Mo.), support an extension to the H-2B program.

“It’s the right thing to do,” Putnam said, arguing that many small businesses rely on the short-term labor the visas provide.

Putnam complained that the H-2B legislation was being held hostage while Democrats tried to use it to leverage a larger immigration bill.

“It’s wrong to use vital legislation designed to protect small businesses and their workers as leverage for other reforms,” Putnam said. “This approach only punishes those who play by the rules and doubly so in this challenging economic climate.”

But Bilbray said extending the visa program without enacting new enforcement rules would lead to more illegal immigration because some would overstay their visas. “Of course that is going to be an overriding issue,” he said. “We need to prove we can enforce the law.”

Bilbray added that he wouldn’t support any more visas unless existing immigration programs are shrunk.

“It can’t just be add-on, add-on, add-on,” he said.

Rep. Steve King (R-Iowa), another immigration critic, derided the H-2B issue as just another piece of last year’s failed Senate package. “Slivers of that comprehensive immigration reform are starting to come forward one at a time for the special interests that were willing to sacrifice the rule of law,” King said.

King also ridiculed the idea that there are not enough Americans willing to do the jobs immigrants would do, given the millions of Americans who are unemployed. “It would be a real shame if they ran out of landscapers,” he said, mockingly. “I’m afraid the American economy will collapse.”

King said supporters of extending the H-2B program without enforcing immigration rules in the workplace are ignoring “the shutdown of the Senate switchboard” last year, and he said GOP leaders should reconsider their support.

Supporters of the visas say that without more immigrant workers, U.S. jobs will be lost and businesses will disappear.

Rep. Charles Boustany (R-La.), who is leading the discharge petition effort on the Stupak bill, said a labor shortage has shut down businesses in his district. “Sugar cane is not being processed in my district. Rice is not being milled; it’s not being bagged. … Crawfish, shrimp, fish, crabs are being turned away by processors because they don’t have workers to clean and pick the catch.”

And Rep. Jim Gerlach (R-Pa.), who lamented the impact on Pennsylvania landscaping businesses, said he saw no discrepancy between opposing illegal immigration and backing the H-2B program. “It’s apples and oranges,” he said. “Folks in my district feel very strongly that we should not allow illegal immigration,” he said, but added that people in the H-2B program are playing by the rules. “Most members of my district have no problem with that,” he said.

It’s unclear what impact the internecine GOP sniping will have given that Democrats control the agenda, although the support of GOP leaders means there is room for at least limited immigration legislation this year that would get broad bipartisan support.

The Stupak bill has been effectively held hostage by Democratic leaders and the Congressional Hispanic Caucus, which wants a deal including temporary visas for illegal immigrants. GOP leaders have decried any visas for illegal immigrants as a form of amnesty. The seasonal workers are used in a variety of industries, from tourism to agriculture to landscaping, but the cap of 66,000 such workers has long since been reached. A provision allowing returning H-2B workers expired last year, squeezing employers, and the program is set to expire.

Backers of H-2B programs such as Stupak note that employers must first advertise for the jobs to see if Americans want to take them, although critics say Americans would take the jobs if they paid higher wages.

The GOP leadership has strongly endorsed a discharge petition on an enforcement-only bill sponsored by Rep. Heath Shuler (D-N.C.), which has reached 185 signatures, while support for the discharge petition on the H-2B bill has been far more tepid, with just 20 signing on so far.

Boehner spokesman Michael Steel declined to comment on the split, seeking instead to keep the spotlight on Democratic leaders, who have blocked both Shuler’s and Stupak’s bills from coming to the House floor.

“The failure of the House to move sensible immigration legislation — including both H-2B visas and increased border security — is entirely the fault of the House Democratic leadership because they insist on including amnesty provisions that are unacceptable to the American people,” Steel said.

But a House Democratic leadership aide said Republican divisions have stymied immigration legislation in the past. “We’ve seen this movie before: When it comes to immigration, Republicans can’t stop fighting amongst themselves. Every time the subject turns to immigration, Sen. [John] McCain [R-Ariz.] and his fellow Republicans turn on one another and it becomes difficult to make progress.”