* Tough talk wows Republican base, alienates Hispanics
* Obama won 67 pct of Latino votes, and the White House
LAS VEGAS, Oct 18 (Reuters) - Republican presidential hopefuls ratcheted up their tough talk against illegal immigration in a debate on Tuesday in Nevada, a state where they might need Latino voters to win the White House.
Fierce opposition to illegal immigration and tough border control is one of the party's hot-button policy issues. But some of the talk on the issue -- and the focus on sealing the border with Mexico -- does not go down well with Latino voters.
Whoever becomes the nominee to oppose President Barack Obama's re-election bid next year will need support from Latinos -- the largest and fastest growing U.S. minority group -- to win the White House.
In 2008, Obama defeated Republican John McCain by more than a 2-1 margin among Hispanics -- 67 percent to 31 percent, and became president. To win in 2012, his opponent likely would need to increase the Republican share to 40 percent, matching the more immigration-friendly George W. Bush when he was re-elected in 2004.
The Republican hopefuls kept up their hard talk on illegal immigration in Tuesday's debate in Nevada, one of the swing states where the 2012 election will likely be decided, and where 27 percent of the population is Hispanic.
Texas Governor Rick Perry said he would use predator drones along the Mexican border, and advocated sending additional troops to patrol the frontier.
Perry also blasted former Massachusetts Governor Mitt Romney for using a lawncare company that hired illegal immigrants, and Romney lashed back at Perry because he had not supported building a fence all along Texas's 1,300-mile (2,000-km) border with Mexico.
Businessman Herman Cain, who has emerged as a frontrunner in the nomination race, was asked about his comment that the United States should build an electrified fence along the Mexican frontier, with barbed wire on top.
Cain said during the weekend he was sorry if his remarks had offended anyone, but said he was not walking away from the idea. "I don't apologize at all for wanting to protect the American citizens and to protect our agents on the border. No," Cain said on Tuesday.
Congresswoman Michele Bachmann said she would fence the entire Mexican border and lashed out against foreign women who come to the United States and give birth to children as "anchors" on which they base their claim to stay.
"I will build the fence. I will enforce English as the official language of the U.S. government," Bachmann said.
Romney eventually interrupted the fierce discussion to take a cooler tone.
"I think it's important for us as Republicans on this stage to say something which hasn't been said. And that is I think every single person here loves legal immigration. We respect people who come here legally," he said.
But damage may have been done.
Robert Zavala, a Las Vegas resident who is a registered Republican, reminded the panel that not every Latino is in the country illegally. "What is the message from you guys to our Latino community?" he asked.
Democratic political strategist Donna Brazile said the issue will haunt the Republicans. "If one of these candidates wants to become president of the United States, they will have to reach out to Latino voters," she said on CNN.