WASHINGTON, May 25 (Reuters) - The biggest proposed overhaul of U.S. immigration laws in a generation won bipartisan approval from a powerful Senate committee last week, but there is a strong chance that Republicans in the House of Representatives will end up killing it.
The problem: House Republicans are far from convinced by arguments from party leaders that passage of the bill would help Republicans draw support from Hispanic voters. Many also believe any kind of amnesty for the estimated 11 million immigrants who are in the United States illegally is just plain wrong.
"There is no evidence to support this idea that Republicans will pick up a lot of votes if we give amnesty to 11 million folks," said Representative Tim Huelskamp, a Kansas Republican.
One possibility is that the House will vote for watered-down reform, including more visas for highly skilled workers. But it likely will not include a way for the undocumented to stay legally and eventually get on a special pathway to U.S. citizenship.
Senate Democrats and even some Senate Republicans say there is no way a comprehensive immigration bill could win final congressional approval without a pathway to citizenship.
"It's a non-starter," said Democratic Senator Charles Schumer of New York, a member of the Gang of Eight senators who wrote the bipartisan Senate bill.
Some House Republican lawmakers say that even if the party would gain votes by supporting sweeping reform, that's no reason to back otherwise objectionable legislation.
"I don't think we should be worried about the political impact but instead what is in the best interest of America," said Republican Representative Mo Brooks of Alabama.
Besides, he said, "People who are going to break our laws, I don't want them in this country."
This kind of opposition from House Republicans may pose the biggest threat to White House-backed legislation set to come next month before the full Senate, which Obama's Democrats hold, 55-45.
Republicans control the House, 233-201 with one vacancy. Most Republicans have traditionally opposed legalization as a form of amnesty that rewards law breaking and they see as providing an incentive for further illegal border crossing.
The bill that passed the Senate Judiciary Committee, 13-5, last Tuesday - with support from three Republicans - includes putting illegal residents on a 13-year pathway to citizenship, provided they pay back taxes and a fine, learn English, hold a job and pass criminal background checks.
The measure, backed by business and labor, also would bolster border security and help fill the need for high- and low-skilled workers.
After Hispanics gave President Barack Obama 71 percent support in the 2012 election, the Republican National Committee endorsed comprehensive immigration reform in March, saying that without reaching out to the fastest-growing large segment of the U.S. voting population, the party could say goodbye to the presidency for generations to come.
Two months later, many Republicans remain unconvinced, particularly in the House, where only 39 of the 233 members come from districts that are 20 percent or more Hispanic, according to a recent study by Alex Engler in the Georgetown (University) Public Policy Review.
Huelskamp recalled a private strategy meeting earlier this year where political pollsters offered their findings and advice to House Republicans. "They said, 'Look at the numbers. We have to do something because of the numbers,'" he said.
But Huelskamp noted that Republican Senator John McCain failed to attract much Hispanic support in his 2008 presidential campaign despite having crafted and pushed a sweeping immigration bill the year before that was ultimately rejected.
McCain picked up 31 percent of the Hispanic vote in 2008 against Obama, just 4 percentage points more than 2012 Republican presidential nominee Mitt Romney ended up with against Obama four years later.
Brooks said the political benefit to Republicans should not matter.
"We can't afford to give amnesty to every person who wants to illegally cross our borders," he said. "We don't have enough money in our piggy bank. Amnesty begets more amnesty.
"I cannot in good conscience ratify illegal conduct with my vote. Any Republican who advocates ratifying illegal conduct with their vote is subverting the very principles that made the United States a great nation."
Few Republican strategists claim the party will gain many votes any time soon among Hispanic voters simply by supporting immigration reform. But most think it important to at least avoid the image of being anti-Hispanic or anti-immigrant so that they can eventually build a base of support among Hispanics.
"We have to have immigration reform to neutralize the charge that we are anti-Hispanic," said Ron Bonjean, a former Republican congressional leadership aide turned political strategist.
"If Republicans refuse to pass comprehensive immigration reform, we will become obsolete as a party within 10 years," Bonjean said.
Representative Raul Labrador, an Idaho Republican and a member of a group of eight House members seeking to craft a bipartisan bill of their own, said: "We aren't going to win any votes if we do immigration reform. But we might actually do the right thing for America, which is the most important thing."
According to a Washington Post-ABC poll released on May 24, 58 percent of all Americans support a pathway to citizenship for those in the country illegally but 52 percent of Republicans oppose it.
Among these Republicans, 67 percent said they could not back a congressional candidate who voted for it. The poll of 1,001 adults was conducted May 16-19, and has a margin of error of plus or minus 3.5 percentage points.
At this point, the bipartisan measure - crafted by four Democrats and four Republicans - is expected to win passage in the Senate, which Democrats control, 55-45.
Then it moves to the House.
"I think the House will pass immigration reform," said Representative Lamar Smith, a Republican from Texas. "I doubt it will include pathway to citizenship."