A fierce battle for the very soul of America is set to begin in less than 24 hours, as the nation gears up to elect its 45th President – the identity of whom no one seems to be able to predict even at this late hour.

Both contenders for the most powerful office in the world, Democratic incumbent Barack Obama and Republican challenger Mitt Romney, meanwhile kept up their campaign blitzes in the all-important swing states, states such as Ohio that may well be the deciders in this knife-edge contest.

By the time counting is completed late on Tuesday night, however, both of their fates will be sealed after the “youngest democracy in the world” witnesses anywhere between 150 to 180 million Americans head to the voting booths and decide whether the last four years of “hope and change” truly delivered on that promise.

The stakes could not be higher. If Mr. Romney wins, he has promised to repeal on his “first day in office,” some of the landmark reform policies introduced by Mr. Obama, including the latter’s game-changing healthcare reform package. If Mr. Obama succeeds in his re-election bid, he will have an opportunity to consolidate his presidential legacy, and likely press on with attempts to overhaul difficult policy areas such as comprehensive immigration reform.

Yet the opinions of voters could not be more divided, nor the race any tighter. While President Obama opened the campaign season on a strong footing, earlier even touching an all-time approval-rating high of 60 per cent, his team of advisers from his old days in Chicago have watched with consternation as Mr. Romney, a former Massachusetts Governor, has torn into his lead.

On the eve of the election and after months of a bitter, personalised campaign, the two men were tied at the national level at close to the 50-per cent mark, according to a wide range of polls. Along the way, women’s reproductive rights, the deportation of undocumented workers, and income inequality across class divisions became points of strident campaign rhetoric.

However on Monday Rasmussen Reports gave Mr. Romney a one-per cent lead over Mr.Obama, who got 48 per cent. General election polls by CNN and Politico claimed a tie between them at 49 and 48 per cent respectively. The Pew Research Centre, NBC news and ABC news respectively announced poll results showing a 1-3 per cent lead for Mr. Obama.

Given the quirks of the U.S. election system though, the outcome in swing states matters far more to the final choice than in states classified as “blue” or “red,” or already strongly in favour of one candidate. Unlike India’s first-past-the-post criterion based on the popular vote, the Electoral College votes in each state are awarded to one candidate based on winner-takes- all. 270 Electoral College votes are required to secure the presidency.

Both contenders appeared to be acutely aware of this reality, reflected in their intense campaign focus on Ohio, Florida, Pennsylvania and Iowa – without which no Republican has won the presidency. Although Pennsylvania has thrown itself behind Democrats in successive recent elections, Mr. Romney made a surprise play for the Keystone State in the final hours before voting began, a gambit that the Obama team decried as a “desperate ploy,” but could also represent the Republican hope that the state was truly pivoting towards their party.

For Mr. Obama, who has spent the recent days not only battling his rival but also bolstering recovery efforts after Hurricane Sandy ravaged large swathes of the East Coast, the few days of his last ever campaign were marked by nostalgia.

Jennifer Psaki, an Obama campaign manager and former Deputy Communications Director at the White House, said, “This is a family. There are a lot of laughs. And a lot of nostalgia on the ups and downs, the incredible rollercoaster that this journey has been from the day he announced he was running.”

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