AUSTIN, Texas — The Barnes & Noble in McAllen was nearly empty when Bill Clinton dropped in unannounced a few months ago, just before Thanksgiving. The few evening shoppers snapped open their cellphones, and within 15 minutes, the place was mobbed.

The former president, having finished a private fundraiser for wife, Hillary Rodham Clinton, seemed unsurprised that a huge crowd had abandoned their dinner plans to shake his hand in the bookstore. He said this place has "treated me well, and it's treated my wife well."

In more than 30 years of political organizing in South Texas, and with four trips in the past 16 months, the Clintons could write chapter and verse about the Rio Grande Valley. Barack Obama, who has never been south of San Antonio, is just opening the cover. And that very fact could help determine the outcome of Texas' March 4 primary fight between Clinton and Obama.

"I'm thinking that the closest thing we've ever had to a Hispanic president is Bill Clinton, and we certainly appreciate that he's been there for us," said Billy Leo, mayor of La Joya, Texas, and a political touchstone. "We don't know Obama."

Historically in Democratic primaries, Latinos make up about 25 percent of Texas voters. But turnout in this year's primaries has broken records. In California, the percentage of Hispanics almost doubled on Super Tuesday, and they voted 2-to-1 for Clinton.

Whether Obama can mitigate the simpatico feelings between Latinos and the Clintons in Texas is a large concern for his time-challenged campaign. The Clintons will rely on surrogates trusted by Hispanic voters — including Henry Cisneros, former housing secretary and San Antonio mayor — and their record on issues of top concern to Hispanics, such as education. Obama is collecting endorsements of his own but faces a steep challenge.

Cisneros pointed out that Hillary Clinton was first in South Texas registering Latino voters for George McGovern in 1972. She was the first lady of a neighboring state (Arkansas) and a friend to Hispanics while in the White House.

"I'm going to be walking a lot of blocks, talking to a lot of groups and shaking a lot of hands," Cisneros said. "My thought is that Texas will be one of her best states."

Complicating Obama's task is long-standing political competition among black and Hispanic political leaders that may make it tougher for a black candidate to win Hispanics voters.

Illustrating that tension, last week, Jesse Diaz — president of the Dallas-area League of United Latin American Citizens — suggested on a Dallas blog that Latinos will respond to Obama with the same "distaste" that some black leaders in Dallas have shown toward Hispanics.

Obama spokesman Josh Earnest said those are the kind of divisions that Obama is showing he can overcome.

"He ended up getting more white support in South Carolina than anyone thought he could. And in California and Georgia as well," Earnest said.

He pointed out that Obama won the majority of Latinos in Illinois and 45 percent in Arizona last week.

"The core of this campaign has been his talk about bringing this country together, and that's useful in preventing a lot of certain divisions that sometimes can crop up in Democratic primaries," Earnest said.

To that end, the Obama campaign is reaching out to the Latino community. It has named political strategist Adrian Saenz — U.S. Rep. Ciro Rodriguez's chief of staff — its Texas campaign director. It has signed on state lawmakers, such as Rafael Anchia of Dallas, and intends to tell Obama's story as a civil rights organizer for Hispanics in Illinois.

"We're going to have to start at the beginning, and we're going to have to introduce Senator Obama to Democratic voters in Texas," Earnest said.

He will travel the state, use TV and radio — in English and Spanish — and particularly talk to younger Latinos, who don't have a history with the Clintons and might be attracted to his message of change, Earnest said.

But the campaign is aware that the Clintons together are a formidable opponent with a long head start.

"If you look at polling on how warm or cold Latinos feel toward a certain person or concept, Bill Clinton ranks ahead of the Catholic Church," Anchia said.

State Rep. Juan Garcia, D-Corpus Christi, is a friend of Obama's from their days together at Harvard law school and intends to open doors for him all around his district.

"Make no mistake about it — Hillary Clinton may be the most well-known woman in the world. That's what we're up against," Garcia said. "It's going to be up to each of us to make that introduction and make it as powerful and as soon as possible."

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Early voting begins in a week.

But in spite of that, the Illinois senator has some advantages among Texas Hispanics, Anchia said.

Obama's background as the son of an immigrant, his life experiences abroad, his work in civil rights and his appeal to younger voters might resonate "in the Latino community in Texas, (which) is one of the youngest communities in the country," Anchia said, adding that the average age of Texas Latinos is "somewhere around 25 years old."

"There's going to be sort of a generational split," he said. "He may not win all of them, but he's going to run very competitively."

Anchia also noted that there are more Latino voters in Houston, El Paso and Dallas — urban areas where Obama tends to do well — than in South Texas.

The lawmaker said he has told the campaign that Obama will need to make personal appearances and hammer on his support of comprehensive immigration reform, as well as his positions on affordable health care and tuition aid for universities and community colleges that resonate with the Latino community.

"We're going to try to get him to (places) where Latinos can see, feel, touch and listen to him," Anchia said.

Both campaigns said some of Clinton's strength among Latinos will be somewhat offset by Obama's support among black voters and the young. The battle will be on to engage voters.

"There are delegates all across the state that are up for grabs," said Earnest, the Obama spokesman. "It's our intention to have a truly statewide campaign."

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