Republican presidential candidate John McCain and his wife have cast their votes in Phoenix, Arizona.

After campaigning coast to coast on Monday, Sarah Palin caught a few winks on a red-eye flight to her home state, where fresh snow glistened in the early-morning moonlight as the temperature hovered around 14 degrees.

Palin voted early this morning inside the tiny City Hall building where just six years ago she presided as mayor of this once unknown frontier town outside Anchorage. Proudly donning her “I Voted Today” sticker, the Alaska governor delivered a short statement to reporters and took a few questions before she heads to Phoenix to find out whether she’ll become the first female vice president of the United States.

It’s been a whirlwind couple of months for Palin, who has fallen under perhaps more scrutiny than any vice presidential candidate in the nation’s history. But as usual, she portrayed an almost mystifying sense of calm, considering all that she has been through in such a relatively short time.

“So we have a very optimistic, very confident view of what’s going to happen today, and again, so glad to get to be home in Wasilla to cast this vote,” she said. “Because forever I'm gonna be Sarah from Alaska. And it’s an honor to get to be here with my friends and family.”

Palin refused to divulge whom she voted for in the Alaska U.S. Senate race between Republican incumbent Ted Stevens — who was recently convicted on seven felony corruption charges — and Democrat Mark Begich.

After the early morning vote, Palin stopped by “Mocha Moose,” one of her favorite drive-through espresso shops, which dot the strip malls around Wasilla.

A reporter asked Palin about what her future role in national politics will be, whether she wins or loses this election. The Alaska governor — who has delivered some of the most partisan barbs of this election cycle — gave an answer that was fitting to the setting, where many residents here know her as a non-ideological problem solver, rather than a socially conservative firebrand.

"You know, if there is a role in national politics it won’t be so much partisan,” Palin said. “My efforts have always been here in the state of Alaska to get everybody to unite and work together to progress this state … it certainly would be a uniter type of role.”

U.S. Presidential Election 2008

Long lines and waiting hours outside polling stations across the United States early Tuesday, the official Election Day, and the number of people who have already cast their votes further indicate that voter turnout this year is expected to be fairly high.

"We opened the doors at 6 a.m (EST), but many people were already lining up outside," said Piere Lee at a fire station-turned-polling station in Arlington, Virginia, "It seems that Americans are fairly enthusiastic about voting this year."

Statistics show that voter registration numbers are up 7.3 percent from the last presidential election.

Democrats, in particular, saw their registration numbers increase by 12.2 percent, while Republicans saw their ranks grow by only 1.7 percent, according to a recent analysis by The Associated Press.

Extra ballots and additional touch-screen machines have reportedly been dispatched by voting officials across the country. Still, observers worry that those efforts are not enough.

Many experts had earlier predicted that voter turnout this year will be the highest in decades.

Some political observers predict early and absentee voters will make up about 30 percent of the total voters on Election Day -- which could approach a record 130 million to 140 million.

"We have a system that is traditionally set up for low turnout," Tova Wang of the government watchdog group Common Cause was cited by local media as saying.

Record numbers have already cast ballots in early voting. As of Monday, more than 24 million had cast their votes. Election experts predicted more than a third of the electorate would have voted before the polls opened on Election Day.