LIVE OAK, Texas -- Nibbling on her breakfast burrito at the tiny Los Charros eatery in a middle-class suburb of San Antonio, Kathryne Short doesn't look like Sen. Hillary Rodham Clinton's worst nightmare.

But that is exactly what she is -- despite being 42, female, Hispanic and earning less than $50,000 a year. That's a demographic profile that, in Texas and nationally, has reliably supported the New York senator in her quest for the Democratic presidential nomination.

"I really like Hillary," Ms. Short said, hesitating slightly. "And I was going to vote for her, mainly because of her gender, and because I admire her -- all the things she's done. But I saw Barack Obama on television last night when he came to San Antonio and boom!

"That was it for me. I'm not sure why, exactly, but there was something about him that really spoke to me. I'm not sure this country is ready for a woman president, but a lot of the things Obama said seemed possible."

That kind of overnight conversion is happening all over the Lone Star State these days, as Sen. Barack Obama, who didn't do much to woo the state's Hispanic voters until recently, draws huge crowds and is finding younger, well-educated, upwardly mobile Hispanics -- especially those scattered in the metropolitan areas of San Antonio, Houston and Dallas-Fort Worth -- falling eagerly into line behind him. His supporters say he can win as much as half the Hispanic vote.

That's bad news for Mrs. Clinton, who must win the Latino vote by a large margin in order to prevail in the March 4 Texas primary, which yields 228 delegates -- the second largest treasure trove in the country.

During the past two weeks, she has been courting Hispanic voters in the older, settled communities of the Rio Grande Valley in South Texas.

In sheer numbers, there aren't as many Hispanics in South Texas as there are in the state's northern cities, but in the booming Rio Grande Valley communities of Brownsville, Edinburg and McAllen -- frequently cited as one of the fastest growing cities in the country -- her supporters have remained steadfast.

"Up north, the Hispanics have fewer roots in the urban and suburban communities around Dallas and Houston and are less tied to the old ways," said Harvey Kronberg, editor of The Quorum Report, a widely read Texas political newsletter and news service. "But in the Valley, she's still strong."

There, the political culture is more rooted in tradition, he said, and political leaders -- mostly judges and sheriffs, many of them veterans of civil rights struggles in the '60s and '70s -- still respect the Clinton name and still call the shots.

The old party boss system of "patrons" and "politiqueros," who walk the block on Election Day handing out bags of groceries in exchange for votes, persists, if in somewhat diminished form, Mr. Kronberg said.

You could see plenty of these older party leaders hopping out of large shiny SUVs at rallies last week in Hidalgo, Brownsville and Laredo. While the audiences were far smaller than those at Mr. Obama's Dallas and Houston rallies, they responded exuberantly when Mrs. Clinton stressed her longtime connections to the region.

In 1972 she lived in Austin and San Antonio while registering voters for George McGovern's presidential campaign. She's also collected a string of endorsements from four of the state's six Hispanic congressmen and from Henry Cisneros, who served as secretary of Housing and Urban Development in President Bill Clinton's administration and who remains a dominant Latino political figure.

"She's basically staked out everything below the I-10 corridor," said Paul Burka, a political columnist with Texas Monthly Magazine, referring to the interstate that snakes across the state from Houston through San Antonio and west to El Paso.

Mr. Obama is counting on a coalition of black voters in Houston and Dallas and the liberal white vote in Austin and other affluent enclaves while Mrs. Clinton struggles to hold on to "Anglos" making less than $50,000 a year in the suburbs of Dallas and Houston.

But Mr. Obama isn't counting out Hispanics either, placing his Texas campaign field operations in San Antonio -- a city "that isn't sure if it wants to be South Texas or one of the state's sophisticated urban centers," Mr. Burka said. That move prompted some fence-sitting local Hispanic politicians to jump into the Illinois senator's camp.

Mr. Obama has also won the support of one of the state's up-and-coming state representatives, Rafael Anchia, who has been talked about in local media here as possibly the state's first Hispanic governor.

"Mr. Obama's personal story is what resonates with me," said Mr. Anchia, speaking on the phone from his Dallas office. Mr. Anchia's father is from Spain and mother is from Mexico. "The fact that Mr. Obama is the son of immigrants, and grew up to go to Columbia and Harvard Law School affirms for me that the American dream is still alive," he said. "And I think that's a message that resonates with a lot of young Latinos here.

"Plus, this community isn't as invested in the Clintons as others might be, and the Obama campaign thinks it can compete with this group in Fort Worth, Houston and Austin," he added, noting that the Obama campaign is betting it can win 40 to 50 percent of Hispanic voters statewide. "If you win Hispanics in those cities, you're doing very well, and you can match Sen. Clinton's prowess south of I-10."

This younger generation of Hispanics is also participating in a Democratic renaissance of sorts in Dallas, a trend that may spread to Houston and other urban areas, he and other experts noted. After years of marginalization by Republicans, beginning with then-Gov. George W. Bush, Democrats swept the Dallas courthouse races in 2006, beating Republicans in more than 40 contested races, said Kirk McPike, a Democratic party operative. .

"It didn't happen by accident," he said, noting that an aggressive voter registration drive, the city's urban renewal and an influx of well-educated young people -- many of them Hispanic -- living in the city's downtown has contributed to gains by the party in Dallas. If those young people are the ones who stood in line last week to cast early votes for Obama, he won't say, but Mr. Anchia believes they did.

Even if Mrs. Clinton wins overwhelmingly in heavily Hispanic districts, another obstacle stands in her way: Texas's weirdly convoluted system for apportioning delegates among its 31 state Senate districts. It seemed a fine idea at the time 20 years ago to reward districts that could show high voter turnout with more delegates. But with this year's primary so important, some political leaders are complaining that the party's rules discriminate against Hispanics, who historically don't vote in great numbers while the state's two black districts -- in Houston and Dallas -- do.

There are several reasons for that disparity, Mr. Anchia said. In Dallas, for example, the average age of Latinos is 26, and 50 percent of that city's Hispanic population is under age 40. "A lot of them don't start voting until they're in their 30s, when have they house payments and responsibilities," he said. Plus, only an estimated 40 percent are eligible to vote anyway, with the rest either documented or undocumented aliens.

"In South Texas, they're terrible about voting," added Mr. Burka. In 2006 in Hidalgo County, where Mrs. Clinton held her rally last week, only 16.5 percent of the population turned out to vote. Numbers were equally low in neighboring Webb and Brownsville counties, he added. And given that Texas is expected to grow from 22 million to 50 million between now and 2040, and of that number, 76 percent will be Hispanic, "this is a real problem," Mr. Burka said.

All of this means Mrs. Clinton could win the popular vote overwhelmingly in the state's seven Hispanic districts -- but end up with as many as three to four times fewer delegates than Sen. Obama.

There's more: what Mr. Obama has laughingly called "The Texas Two-Step," a hybrid primary caucus system which requires that two-thirds of the delegates be elected based on the popular vote in those state Senate districts, with the remainder selected in caucuses held on election night .

That means in some districts, voters must vote twice -- once at the polls, either on Election Day or during two weeks of early voting, and then a second time at a party caucus after the polls close. What might be a political joke's punchline in Philadelphia or Chicago is taken deadly seriously here: "Don't forget to vote twice!" read one flyer handed out before an early vote rally in Hidalgo Thursday night, complete with detailed directions to local caucus location.

Finally, the generational divide that has been playing out all over the country in the Obama-Clinton race is present, too, in Hispanic families. On the one hand, there's Jerry Rodriguez, a county commissioner in Goliad, who mournfully shakes his head when asked about younger supporters bucking their elders, who generally support Mrs. Clinton.

"It's true, there is a split, but I don't know what the young people see in him," said Mr. Rodriguez of Mr. Obama. "She's been through so much, has so much experience and everything about her makes me feel she's more qualified."

The Rio Grande Valley may be economically diverse, with big box stores and huge auto dealerships lining Route 83, and McMansions sprouting up in farm fields, but there are plenty of low-income Hispanics who, worried about education -- dropout rates are nearly 50 percent here -- illiteracy, immigration reform, jobs and health care, have responded favorably to Mrs. Clinton's specifics.

"I can say nothing wrong about Sen. Obama, but there's no substance to what he says," said Felix Rodriguez, commander of District 18 of the Veterans of Foreign Wars, who was standing outside the arena in Hidalgo after Mrs. Clinton gave her speech. "I support Mrs. Clinton's policies. We need a veterans' hospital in the Rio Grande Valley, we need immigration reform, and she's what we need in Washington."

"Plus," he added with a wink, "she stood by her man."

Then again, there's Matthew Garcia, 28, of San Antonio, who, when he's not teaching theatre, conducts tours via Segway -- the two-wheeled, electronic personal transportation mover -- along the city's historic Riverwalk. He supports Mr. Obama for reasons that he can't quite articulate -- "I think we need a change, and I like the vibrancy I'm seeing in his campaign" -- while his parents are supporting Mrs. Clinton.

"We talk about it a lot, and it's true, the older Hispanics I know are all the same way. But I have to say none of us will feel really terrible if one or the other wins."

There's another, hidden issue driving the split in support among Hispanics, added Nancy Reyes, 33, of McAllen, who attended the Hidalgo rally Thursday.

"It's race," she said. "I think younger people are trying to keep an open mind, but the older ones still are pretty suspicious of a black man. It's the way my parents raised me," she said, shrugging.

Ms. Short couldn't disagree more. "I think Hispanics have gotten past that, and are really looking at Obama differently. I think people are relating to him on a minority to minority level."

Still, all of them seemed plenty pleased that Texas will be in the national spotlight for the next week and a half. Early voting has broken all records, and last week the state's Democratic Party chairman, Boyd Richie, predicted that 2 million people would turn out to vote on election day -- the largest number since 1984.

"This is an incredibly exciting time to be in politics in Texas," said Josh Berthume, who edits thetexasblue.com, a progressive blog. "This is a dynamic that has been imagined and talked about for a long time, but never realized at this level of excitement. People are marveling at images on the web of conference rooms full of paid presidential campaign staffers, right here in Texas. It's really something."

Page One. In this story as published Feb. 24, 2008 about the March 4 Texas primary, Josh Berthume's name was spelled incorrectly. Also, the correct name of his Web site is www.TheTexasBlue.com.