Democrat Barack Obama and Republican John McCain have cast their votes, but the rivals in the race to the White House haven't stopped campaigning in the waning hours of the 2008 election campaign.

"I voted," Sen. Obama told reporters and onlookers to a round of applause after casting a ballot in his Chicago neighbourhood. He was accompanied by his daughters and wife, but he didn't remain in Illinois long. After voting he headed to Indiana to make a last minute pitch to voters.

It was a similar scenario in Arizona, where Sen. McCain voted with his wife Cindy before preparing to head to campaign stops in Colorado and New Mexico. Despite polls showing him down by four or more points nationally, McCain remained optimistic at a rally in Colorado Tuesday afternoon.

Recent polls show Obama leading McCain by a small margin in the battleground state, but a fired up Republican candidate rallied his supporters with Cindy McCain and Senator Joe Lieberman at his side.

He urged supporters to bring all their friends and family members to the polls, adding "drag them if you have to!"

"I feel the momentum, I feel it, you feel it, and we're gonna win this election, and we're going to win it right here in the state of Colorado," said McCain. He added, "The Mac is back!"

A Democratic presidential candidate has won Colorado just once since 1976, when Bill Clinton won in 1992. Al In 2000 and 2004, Al Gore and John Kerry, respectively, lost to George W. Bush.

There are nine electoral votes are at stake in Colorado.

McCain running mate Sarah Palin flew back to Alaska last night where the state's governor cast her vote today. Sen. Joe Biden voted in his home state of Deleware, with his 91-year-old-mother at his side.

Record turnout

People across the U.S. began lining up at sunrise on Tuesday to cast their ballots in a historic election that is predicted to see a record voter turnout. As many as one third of voters may already have cast their ballots in early voting, relieving some of the pressure on elections workers today. But many states are still reporting long lineups. Others, such as Virginia and Pennsylvania have reported some delays because of issues arising from electronic voting machines.

If Obama wins, he will become the first U.S. president of African-American descent. If McCain wins, Palin will become the first female U.S. vice-president.

Obama, a 47-year-old first-term senator from Illinois, was leading in most polls as of Tuesday morning against the 72-year-old McCain, a veteran lawmaker who spent five-and-a-half years as a PoW in Vietnam.

McCain has touted his experience and "maverick" image in Washington throughout the campaign. But his message has had difficulty resonating with voters eager for change, even in traditionally red states like Virginia.

CTV's Washington Bureau Chief Tom Clark said if Obama can win in Virginia, the election will virtually be his for the taking.

"If you're looking for any talisman tonight, I'd keep an eye on Virginia. If Virginia falls to Obama this election is going to be over early tonight," Clark told CTV's Canada AM from Chicago, where Obama had his election night headquarters.

"In Virginia they haven't voted Democrat since 1964, and that was for (Lyndon Johnson), so that would be a massive turnover to the Democratic side. And it would be Virginia, the home of the Confederacy, that would put the first African-American into the White House. The irony is kind of delicious."