WASHINGTON (CNN) Update: Sen. Hillary Clinton used her big win in West Virginia on Tuesday to make her case that she has a better chance of beating the Republicans in the general election.
"I am more determined than ever to carry on this campaign," she told supporters in Charleston, West Virginia.
"I am in this race because I believe I am the strongest candidate. ... I can lead this party to victory in the general election if you lead me to victory now."
With half of the results in, Clinton was ahead of Sen. Barack Obama by a margin of more than 2-1.
Clinton has faced calls to drop out of the race because she trails Obama in delegates won, states won and the popular vote this primary season.
Clinton also now trails Obama when it comes to the support of superdelegates, and her campaign is $20 million in the red.
Howard Wolfson, Clinton's communication director, said the New York senator is "in until the very end."
"We think we're going to be the nominee. We're going to make our case to the superdelegates," he said.
In an e-mail to supporters, the Clinton campaign called West Virginia a "tremendous victory".
"It's clear that the pundits declaring this race over have it all wrong. The voters in West Virginia spoke loud and clear -- they want this contest to go on."
Clinton's win won't do much to cut into Obama's lead: West Virginia had just 28 delegates at stake, and those will be awarded proportionately.
Her campaign argues that she can catch Obama in the popular vote by turning out the vote in the remaining five contests.
Clinton has also continued to tout her electability, saying she's more fit to go up against Sen. John McCain, the presumptive GOP nominee, in November.
"I'm winning Catholic voters and Hispanic voters and blue-collar workers and seniors, the kind of people that Sen. McCain will be fighting for in the general election," Clinton said earlier.
Reiterating a point she has made frequently while campaigning in West Virginia, Clinton pointed out Tuesday that no Democrat has won the White House since 1916 without winning West Virginia.
Bill Clinton won there in 1992 and 1996. George W. Bush took the state in 2000 and 2004.
In addition to West Virginia, Clinton's campaign points to other swing states she has won -- like Ohio and Pennsylvania -- as they try to woo superdelegates to their side.
"They have changed some minds, but more minds have been changed right now in favor of Sen. Obama," CNN contributor Donna Brazile said.
Obama surpassed Clinton in the race for superdelegates Monday. Clinton led by more than 100 at the beginning of the year.
Obama appeared to be looking ahead of Tuesday's vote toward a general election fight with McCain as he campaigned in Michigan and Missouri.
"There's a bipartisan tradition in foreign policy that we should try to recapture. Unfortunately, John McCain is not going to provide that," Obama said in Cape Girardeau, Missouri.
Both Obama and Clinton have softened their attacks on each other in recent days. Obama has turned his attacks to McCain, and Clinton spoke favorably of Obama in her victory speech Tuesday.
Still, exit polls from West Virginia indicate a strong division among Democrats.
Almost as many of Clinton's West Virginia supporters would vote for McCain as would for Obama, the polls show.
If Obama were the Democratic nominee, 36 percent of Clinton supporters would vote for him in the fall, the polls found.
But 35 percent said they'd cast their vote for McCain instead.
A bare majority of his West Virginia supporters -- 51 percent -- said they would back Clinton in the fall, but 31 percent said they'd vote for McCain.
After West Virginia, the campaign trail moves to Kentucky and Oregon, which vote in one week. Clinton is expected to do well in Kentucky, but Obama is the favorite to win Oregon.
WASHINGTON (CNN) Previously: The outcome of West Virginia's primary Tuesday may best be foretold by where Sens. Hillary Clinton and Barack Obama plan to spend the day.
Clinton is expected to be in Charleston, West Virginia, to celebrate what should be her large victory.
Obama has no plans Tuesday night, but he is spending the late afternoon at a campaign event in Missouri. That state has already voted this primary season but is considered a swing state that Democrats and Republicans have in their sights this November.
Clinton, it seems, is concentrating on the present; Obama is looking to the future.
Polling places in West Virginia opened at 6:30 a.m. Tuesday.
Clinton, from New York, is ahead in West Virginia by an average of 40 points in the most recent public opinion polls.
The small state, with a large population of older voters and blue-collar workers, a dearth of upscale voters and a tiny African-American population, appears to be a perfect demographic fit for Clinton.
But even a landslide victory in West Virginia, which has 28 delegates, may be too little too late to keep Clinton realistically in the hunt for the Democratic presidential nomination. She trails Obama, from Illinois, in delegates won, states won and the popular vote so far this primary season. Clinton also now trails Obama when it comes to the support of superdelegates, and her campaign is $20 million in the red.
Clinton said she's fighting on, telling a West Virginia crowd Sunday that "I guess my favorite message was from a woman named Angela. 'Keep strong,' she said, 'it's not over until the lady in the pantsuit says it is.' "
Like elsewhere in the country, the West Virginia voters are dealing with tough economic times. And that's not lost on Clinton, who is touting her plan, which was first proposed by presumed Republican nominee Sen. John McCain, to repeal the federal gas tax this summer.
"I want to give you a gas tax holiday this summer and I want the oil companies to pay the gas tax out of their record profits," Clinton told West Virginia voters Monday. "Now you may have heard something about this on the news because it's controversial. My opponent, Sen. Obama, says, 'Oh no, that's just a gimmick, that's not going to help people.'
"Well, I gotta tell you, according to the Department of Energy, it will help you [save] $70 this summer, and if you're a truck driver or you commute long distances, it'll help you even more."
But tough talk like that seems to be the exception. Since last Tuesday, when she squeaked out a victory in Indiana but lost by double digits in North Carolina, Clinton appears to have toned down her rhetoric when talking about her rival.
As the long odds to winning the nomination get longer, one thing Clinton continues to do is tout her electability, saying she's the stronger Democratic candidate to go up against Arizonan McCain in November.
"I'm winning Catholic voters and Hispanic voters and blue-collar workers and seniors, the kind of people that Sen. McCain will be fighting for in the general election. Now some call you swing voters, I call you Americans -- and I call you hard-working West Virginians who are trying to figure out what is best for you and your families," Clinton said.
"A big Clinton win will send a powerful message that there are a lot of Democrats not yet ready to get on board with Obama," said Bill Schneider, CNN senior political analyst. He added that a large Clinton victory in West Virginia "could send a sobering message to the Obama Democrats."
Clinton is also using electoral history to maker her case. "I think it's fair to say that West Virginia is a test. It's a test for me and it's a test for Sen. Obama, because for too long we have let places like West Virginia slip out of the Democratic column. And you know it is a fact that no Democratic president has ever won the White House since 1916 without winning West Virginia. That's how important the voters of West Virginia are," Clinton said.
Bill Clinton won West Virginia in 1992 and 1996. George W. Bush took the state in 2000 and 2004.
"West Virginia used to be solidly Democratic, until 2000, when George W. Bush surprised everyone by winning the state. How did he do it? Social issues -- abortion, gays, and most important, guns -- in a state where more than 70 percent of the voters own a gun," Schneider said.
Obama acknowledges he will not win in West Virginia. Monday's single campaign event in West Virginia was his only campaign stop in the state in recent weeks.
He told the audience gathered at the Charleston Civic Center that "I'm extraordinarily honored that some of you will support me, and I understand that many more here in West Virginia will probably support Sen. Clinton."
That was one of Obama's rare mentions of Clinton in his speeches since last Tuesday's primaries. About the only time he uttered the name Clinton this past week was when reporters or voters asked him specifically about her. While he's not taking the nomination for granted, the person who now appears to be in Obama's sights is McCain.
"I have great respect for John McCain's service to this country. I know he loves it dearly and honors those who serve. But John McCain is one of the few senators of either party who oppose this bill [21st Century GI Bill] because he thinks it's too generous. He thinks it's too generous. I could not disagree with him more," Obama told the audience in Charleston.
Obama touted his support of that GI bill, saying the legislation would provide returning veterans with a "real chance to afford a college education."
That's a message that plays well in West Virginia. The state has more than its fair share of veterans, and West Virginians are sympathetic to those who serve in uniform.
After West Virginia, the campaign trail moves to Kentucky and Oregon, which vote in one week. Clinton is expected to do well in Kentucky, while Obama is the favorite to win Oregon.