Beaming from the podium with his wife Cindy by his side, John McCain claimed victory in the South Carolina Republican primary Saturday night, eight years after his quest was derailed in the same state by George W. Bush. His win came in the second competition of a political doubleheader in the White House race.

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Earlier, former Massachusetts Gov. Mitt Romney won the Republican Nevada caucuses, and Sen. Hillary Clinton won Nevada in the Democratic race.

"Eight years is not a long time," McCain said in his victory speech. "What's eight years among friends?"

"In war and peace, in good times and challenging ones, we have always known that the first responsibility of government is to keep this country safe from its enemies, and the American people free of a heavy-handed government that spends too much of their money, and tries to do for them what they are better able to do for themselves," McCain said.

And turning to the economy, and talk of recession, McCain said: "I know and you know we are facing challenging economic times, and we must be responsive to the concerns of Americans who fear they are being left behind in the global economy. But nothing is inevitable in our country. We are the captains of our fate."

With 93 percent of precincts reporting, here's how the Republican race shaped up.

• John McCain 137,467 - 33 percent
• Mike Huckabee 123,467 - 30 percent
• Fred Thompson 65,223 - 16 percent
• Mitt Romney 62,652 - 15 percent
• Ron Paul 15,275 - 4 percent
• Rudy Giuliani 8,586 - 2 percent
• Duncan Hunter 994 - 0 percent
• Tom Tancredo 111 - 0 percent

Former Arkansas Gov. Mike Huckabee, in his second-place concession speech, praised McCain for running an "honorable" and "civil" campaign, "even though we would have liked a different result."

"We left it all on the field. I don't want anyone who worked in this campaign, from our volunteers to our staff, to feel anything other than an extraordinary sense of pride, and also a sense of just sheer joy that we got as far as we did when nobody thought it was even possible for us to be in contention," Huckabee said.

No Republican since 1980 has won the GOP nod without a triumph in the first-in-the-South primary.

Voting machine problems plagued the voting in some South Carolina communities.

In one coastal South Carolina county, as many as 90 percent of the electronic voting machines did not work when polls opened. A State Election Commission spokesman said some of the machines were not properly tested. He said a final step that resets the machine for voting wasn't done, and that prevented them from starting up.

McCain's campaign said it was disturbed by reports that voters were turned away in the morning when the machines were down.

Polling officials in some parts of the state said they believe turnout was heavy early because of forecasts for snow later in the day.

After a poor showing in the Nevada caucus, California Rep. Duncan Hunter is dropping out of the race for the Republican presidential nomination, his campaign said Saturday.

Clinton, Romney Carry Nevada

With all Republican precincts reporting, here's how the Republicans stacked up:

• Mitt Romney 22,649 - 51 percent
• Ron Paul 6,087 - 14 percent
• John McCain 5,651 - 13 percent
• Mike Huckabee 3,616 - 8 percent
• Fred Thompson 3,521 - 8 percent
• Rudy Giuliani 1,910 - 4 percent
• Duncan Hunter 890 - 2 percent

With 98 percent of Democratic precincts reporting, here's how the Democrats stand:

• Hillary Clinton 5,355 - 51 percent
• Barack Obama 4,773 - 45 percent
• John Edwards 396 - 4 percent

While Clinton won the popular vote, Barack Obama took home more delegates, edging her 13-12.

The split verdict resulted from the proportional manner in which delegates were awarded. Obama emerged with one more than Clinton because he ran strongly in rural areas.

Overall, Clinton leads the delegate race with 236, including separately chosen party and elected officials known as superdelegates. Obama has a total of 136, and former North Carolina Sen. John Edwards has 50.

Clinton's victory marked a second-straight campaign triumph for the former first lady, who scored a New Hampshire primary upset last week and is locked in an historic, increasingly tense struggle with Obama.

"Today we won a huge victory by overcoming institutional hurdles and one of the worst negative ads in recent memory," the Clinton campaign said in an official statement.

The Clinton camp also said it received "numerous reports of strong-arm tactics designed to discourage our voters from caucusing and found itself on the receiving end of one of the most scurrilous smear efforts in recent memory."

Obama rejected Clinton's accusations.

"We ran an honest, uplifting campaign in Nevada that focused on the real problems Americans are facing, a campaign that appealed to people’s hopes instead of their fears," Obama said.

"We’re proud of the campaign we ran in Nevada. We came from over 25 points behind to win more national convention delegates than Hillary Clinton because we performed well all across the state, including rural areas where Democrats have traditionally struggled," he said.

Nevada Republicans said the economy and illegal immigration were their top concerns, according to preliminary results from surveys of voters entering the caucuses. Romney led among voters who cited both issues.

Mormons gave Romney about half his votes.

Romney said Republicans had cast their votes for change -- and that he was the man to provide it.

"With a career spent turning around businesses, creating jobs and imposing fiscal discipline, I am ready to get my hands on Washington and turn it inside out," he said in a statement issued while he flew to Florida, site of the Jan. 29 primary.

Texas Rep. Ron Paul said his second-place finish in Nevada showed his message is being heard and that he has more supporters than he thought.

"Millions of people have heard this message and this is why coming in second is very great, it sends a great message," Paul said to loud cheers. He conceded that South Carolina's primary, where he was running a distant fifth, was not his to win.

Paul took several swipes at former New York Mayor Rudy Giuliani, who got fewer votes than Paul in Nevada and was trailing Paul in returns being tabulated Saturday night in South Carolina. He told the audience about a confrontation with Giuliani during this month's debate in South Carolina. He said Giuliani "cut me down."