By John Whitesides

CERES, Calif., Nov 26 (Reuters) - For most Republicans in the U.S. Congress, a large gathering of Hispanic voters to discuss immigration would be politically perilous - an invitation to complaints about the party's longtime resistance to measures aimed at helping undocumented immigrants.

But when Republican Rep. Jeff Denham walked into a meeting with hundreds of his Hispanic constituents at a church in California's Central Valley this month, he was met with applause, praise and a hand-lettered "Thank You" sign.

Denham, 46, is a rarity in the U.S. House of Representatives: one of only three Republicans in the chamber's 231-member majority who support a Democrat-sponsored bill that would give millions of undocumented immigrants a legal pathway to U.S. citizenship.

So far, Denham is a voice in the wilderness of the Republican Party, nationally. But in California, he is closer to the mainstream and represents a path forward for his party that begins by facing the human side of undocumented immigrants and extends to a view that immigrants can drive the economy.

Denham, who said he learned Spanish to help court his wife Sonia, the daughter of Mexican immigrants, recalled watching his father-in-law battle the U.S. immigration system and said he would keep lobbying colleagues in Congress on the issue.

"There are some Republicans who have said some outrageous things" about undocumented immigrants, Denham said after meeting with the crowd in Ceres, a city of 45,000 people. "My job is to make sure the entire party is not branded that way."

Immigration - an issue that gained political urgency for both parties after last year's elections revealed the potency of the nation's exploding Hispanic population - has lost momentum in Washington, overshadowed by debates about federal spending and Democratic President Barack Obama's troubled healthcare makeover.

But in California, home to nearly one-third of the nation's estimated 53 million Hispanics, the calls to revamp immigration laws to deal with 12 million undocumented immigrants nationwide have remained front and center. And Obama has said he wants action on the issue.

For Denham, whose district is 40 percent Hispanic, being a cheerleader for immigration reform is a political necessity, even though it has sparked some criticism from conservative groups that typically favor his party.

For other California Republicans, it could be a step toward viability for a party suffering the political consequences of a boom in Hispanic population and a backlash against Republican-backed immigration laws of the mid-1990s that have since been eliminated. Democrats now hold every major state office in California, and significant majorities in the state's legislature and congressional delegation.

Many California Republicans see their experience as a cautionary tale for the party in states such as Nevada, Colorado, Arizona and Texas, where Democrats hope to turn growing Hispanic minority populations into building blocks for permanent political majorities.

"Republicans at the national level and in other states need to look at what's happened in California, because those demographics will affect the whole country," said Ruben Barrales, president of Grow Elect, a California group that recruits Republican Hispanics to run for public office.

The committee, one of several Republican efforts in California to build ties to the Hispanic community, has helped about 50 Hispanic Republicans win local offices across the state. Barrales hopes to break triple digits next year.

"Given the demographics, there is no way that Republicans get from where they are today to becoming a governing party without winning Latinos," said Barrales, a former presidential aide in Republican George W. Bush's administration. "We've got to change the face of the Republican Party so it's reflective of the demographics of the state."

Nationwide, the Republican share of Hispanic votes in presidential races has dropped from Bush's 44 percent in 2004 to Mitt Romney's 27 percent in 2012: the lowest Republican share since 1996. At the same time, the Hispanic share of the national vote increased from 8 percent to 10 percent and is still climbing.


'A CATASTROPHIC TRAIN WRECK'

In California, Hispanic support for Democrats surged after the passage in 1994 of a Republican-backed ballot measure, Proposition 187, that was designed to block state benefits for immigrants who did not have legal status.

Before 1992, Republicans had won California in nine of 10 presidential elections. Since 1992, they have lost California in all six elections, and the state is now one of the nation's most reliably Democratic.

"The fallout since Proposition 187 has been a catastrophic train wreck for the Republican Party in this state," said Gary Segura, a political scientist at Stanford University and co-founder of the polling firm Latino Decisions.

State Republicans have taken a more moderate tack recently, giving substantial support to a law passed by the California legislature and signed by Democratic Governor Jerry Brown making undocumented immigrants eligible for driver's licenses, one of several bills expanding their rights

National Republican leaders acknowledge the demographic threat to the party and tout an immigration overhaul as the first step to recovery among Hispanics. But the effort has hit a roadblock in the House of Representatives, where it is a hostage to divisions within the Republican Party.

Many conservative Republicans oppose a bill passed by the Democrat-led Senate that would give undocumented workers hope of becoming U.S. citizens.

Such Republicans see the bill as an "amnesty" measure that would reward those who broke the law, take jobs from current citizens and lead to lower wages for all blue-collar workers. Some House Republicans also fear a possible primary challenge from the conservative Tea Party movement if they back the bill.

Denham counters such concerns by arguing the Democratic bill would a $1 trillion boost to the U.S. economy by adding millions of new taxpayers to the system. He also noted that it would create a 13-year process to gain citizenship.

"That's a long time," he said. "It's an issue of fairness."

Obama has called on Congress to act soon on immigration. U.S. House Speaker John Boehner said last week that immigration reform was "absolutely not" a dead issue but he would not say when the topic might surface again.

In Ceres, Denham noted that since he became the first Republican to support a version of the bill offered by House Democrats, two other Republicans - Californian David Valadao, whose Central Valley district is 70 percent Hispanic, and Florida's Ileana Ros-Lehtinen - have backed the bill.

"Call other members' offices," Denham urged those in Ceres. "Ask them why" they aren't supporting an immigration overhaul.

Some who heard Denham's pitch remained wary of the Republican Party's commitment to Hispanics, who play a big role in the Central Valley's labor-intensive farming economy.

"Supporting immigration reform is a big first step, but he needs to do a little more than that," said Victor Orosco, a mechanic from nearby Riverbank, where Denham attended a Spanish-language Mass at a Roman Catholic church and briefly addressed the congregation in Spanish before the Ceres meeting.

Orosco questioned whether Denham and other Republicans who now back immigration reform were making a politically inspired conversion. "Now that they see people going to the other team, now they want to support us," he said.

Brenda Noriega of Fresno, a community organizer for the activist group Faith in Community, said after the Ceres meeting that there was still broad distrust of Republicans among Hispanics.

"We are going to vote for the people who support us," Noriega said, making it clear that conservative Republicans did not qualify.

"In the Latino community, we know the Tea Party," she said dismissively. "We know where they stand."


'A LONG WAY TO GO'

Denham rejected the notion that his stance was a re-election ploy, calling it a commitment to fix an immigration system that has torn families in his district apart through deportations and bureaucratic wrangling.

Denham and other California Republicans said winning over Hispanic voters who distrust their party on key issues such as jobs, the economy, healthcare and education would require becoming a more consistent presence in Hispanic communities and putting a more empathetic face on a party often viewed as out of touch with minorities' concerns.

"Some of the neighborhoods that I've walked over the years, I've been the first Republican who has walked there," said Denham, who was re-elected last year with 53 percent of the vote over Democrat Jose Hernandez, a former astronaut.

Denham appears frequently on Spanish-language television networks such as Univision and Telemundo to promote - and often defend - Republican positions. But he acknowledges the party has a long way to go on immigration.

"Some of my colleagues just say, 'Uphold the laws.' That is a very easy statement to make," he said. "We have a long way to go and a very short time to get there."

He said reaching out to contact Hispanics is difficult for many Republican House members in less diverse districts, saying they "tend to stay in their comfort zones."

Nationwide, only 24 Republicans represent a U.S. House district where at least 25 percent of the population is Hispanic - and 11 of them are in California, according to data compiled by the nonpartisan Cook Political Report.

"If there is any state in the country that really needs to deal with immigration reform, it is California," said Wayne Bridegroom, a Baptist pastor in Modesto who offered a prayer for Denham at the Ceres event.

Andy Vidak, a white Republican cherry farmer who won a special election to the California Senate this year from a Central Valley district that is mostly Hispanic, said winning over Hispanics requires Republicans "to go where Republicans rarely go, and where Democrats take the voters for granted." (Editing by David Lindsey, Peter Henderson and Jonathan Oatis)