WASHINGTON/NEW YORK, Nov 5: As Americans begin voting on Tuesday to elect a new president, Barack Obama appears likely to get a second four-year term at the White House.

But His Republican challenger Mitt Romney remains quite close in the dead heat election.

This also reflects in the lead Mr Obama has built in early and absentee voting in key battleground states. But political pundits who predict his victory acknowledge that it will be a narrow victory as the two candidates seem tied in all opinion surveys.

This has caused some analysts to say that the popular vote could provide a stalemate and the election will be divided in the Electoral College.

The national betting average, published on Monday by Real Clear Politics, shows that the in-trade odd between Mr Obama and Mr Romney stands 66.8 to 33.3. This indicates that the gamblers believe President Obama is twice more likely to get re-elected.

And a projection of early ballots further strengthens this impression.

The US Election Project at George Mason University in Virginia reports that more than 29.5 million Americans have already cast ballots in 34 states and the District of Columbia.

And they gave President Obama a lead in early and absent voting but with not as large a margin as Mr Obama had against Senator John McCain in 2008 elections.

Although early votes are counted after the Election Day, some states offer information about party affiliation of the voters and the university used this information to determine voters’ preferences.

The information shows Democrats leading in four of the five battleground states: Florida, Iowa, Nevada and North Carolina. In Colorado, Republicans have an edge over Democrats, although Mr Obama had won this state in 2008.

Republicans, while commenting on this information, told various US media outlets to note a sharp decrease in Mr Obama’s popularity among early voters. This, they said, was good news for Mr Romney and they were certain that they would overtake Mr Obama on Tuesday.

The Obama campaign, on the other hand, realises that positive news about early voters may cause some of their supporters to reduce their efforts. So they urged them not to do so.

“Tomorrow, everything we’ve been working for and fighting for is at stake,” said First Lady Michelle Obama in a message to Obama supporters.

“So make sure to tell everyone you know to vote, and then help every last supporter get to the polls before tomorrow night.”

Democrats are also telling their supporters in Colorado, where Mr Romney appears to have an edge, that they could turn the tide if they vote in large numbers on Tuesday.

According to the George Mason University, more than 1.6 million voters have cast early ballots in Colorado, with Republicans having an edge of 38,000 votes.

More than 4.4 million voters have cast early or absentee ballots in Florida. About 246,000 more Democrats cast early votes; 87,000 more Republicans cast absentee ballots. Florida has 29 electoral votes and can play a major role if the election is decided in the Electoral College.

In Iowa, Democrats hold an 11-point edge in early voting.

In North Carolina, more than 2.5 million voters have cast ballots, with registered Democrats holding a 47.6 per cent to 31.8 per cent edge over Republicans.

In Nevada, Democrats have a seven-point edge over Republicans in early voting here.

In Ohio, which has 18 electoral votes and has always played a pivotal role in swinging the election for or against a candidate, more than 1.6 million voters have already cast ballots.

Although early voters in Ohio are not required to reveal their party affiliations, data collected from there show a thin edge for Mr Obama.

These four states have a total of 56 electoral votes and can provide Mr Obama a big lead on his way to 146 electoral votes he needs from 11 swing states to win the election.

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