AUSTIN, Texas (CNN) -- It's showdown time in Texas.
The Democratic race was very different when the candidates debated three weeks ago.
Sens. Hillary Clinton of New York and Barack Obama of Illinois will face off in a Democratic presidential debate in Austin Thursday.
The debate, to be held on the campus of the University of Texas, will air live on CNN, CNN International and CNN.com from 8 to 9:30 p.m. ET. The debate will also air in Spanish on Univision at 11:30 p.m. ET.
For both candidates, a great deal is at stake. This is the first time in three weeks that the two remaining major Democratic White House hopefuls have debated. Watch a preview of tonight's debate »
A lot has changed since the two debated in Hollywood, California, on January 31. Just five days later, Clinton and Obama both scored big victories on Super Tuesday, splitting two dozen contests from coast to coast.
But then Obama went on a winning streak, capturing 10 straight contests, including Tuesday's primary in Wisconsin and caucuses in Hawaii. See where the race stands after Tuesday's results »
The momentum in this fight has shifted to Obama, and even former President Clinton admitted while campaigning in Texas on Wednesday that his wife must win in Texas and Ohio when those states, along with Vermont and Rhode Island, hold primaries March 4.
Texas is the biggest prize that day, with 193 Democratic delegates up for grabs.
With so much at stake, Clinton needs a very strong performance in Thursday's debate, the only time the two candidates will share the same stage in Texas before the state's primary. Take a behind-the-scenes look at the debate preparations »
"Texas is the end game. Hillary Clinton has to stop Obama in Texas. This means she has to do something to shake the race up. She has to raise doubts about Obama and get Democrats to rethink whether they really want to rally behind him," CNN senior political analyst Bill Schneider said. Watch how pressure the pressure on Clinton is building »
"So far, the Clinton campaign has tried to do that by portraying Clinton as a fighter and Obama as weak, alluding that Republicans will wipe the floor with him. That message has backfired. Voters are sick to death of all the fighting. They don't want to go back to the Clinton wars of the 1990s," he added.
Obama has a different predicament. He's riding a winning streak and leads Clinton by more than 140 pledged delegates, but he faces some challenges in Texas, a state with a large Latino population. Clinton's done quite well with such voters so far this primary season. Watch what Latinos will be looking for »
"Obama needs to break through to Latino voters in this debate. Latinos know and trust the Clintons. They don't know Obama. Clinton is relying on Latinos as her firewall in Texas. The debate -- broadcast in Spanish on Univision -- is his chance to break through that firewall," Schneider said.
A CNN/Opinion Research Corporation poll out Monday suggests that the Democratic race in Texas is a statistical dead heat.
In the survey, taken before Obama's Tuesday victories in Wisconsin and Hawaii, 50 percent of likely Democratic primary voters support Clinton as their choice for the party's nominee, with 48 percent backing Obama. The poll's margin of error is 4.5 percentage points.
Two other recent polls also show the race statistically even.
"One reason the race appears to be tight is that Texas Democrats are having a hard time choosing between two attractive options," CNN polling director Keating Holland said.
"Likely Democratic primary voters would be equally happy if either candidate won the nomination, and they don't see a lot of difference between them on several top issues."
The economy is among the top issues that could come up in tonight's debate. According to a CNN/Opinion Research Corporation poll out Thursday morning, 62 percent of Texans think the economy's in a recession. And since Texas is a state that borders Mexico, the odds are good that the divisive issue of illegal immigration will come up as well. E-mail to a friend
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