Obama in Columbus, Ohio. (AP)

Springfield (Montana), Nov. 3: A mobile phone was pressed to Senator Barack Obama’s ear as he slouched down in a black leather chair in the front cabin of his campaign airplane. He leaned away from the headrest, where his name is spelled out in blue stitching.

A few miles away, thousands of people streamed into JFK Stadium at Parkview High School on Saturday for a late night rally. But Obama stayed on his chartered Boeing 757 as he spoke by conference call to thousands of his team leaders around the country, the volunteers who form the ranks of an army that he hopes will give him an edge in the waning hours of therace.

As he pressed his right hand to his forehead, his sober expression seemed at odds with the confident gleam in the eyes of his advisers. While Obama smiles less than he once did, gauging his mood simply by looking at him is risky: his baseline cool temperament has seldom spiked along the rocky points of his journey.

In a campaign where he has slogged through more competitive election days than any recent nominee, only one more lies ahead.

And it is the long path of the Democratic primary, which lurched from the ups of Iowa to the downs of Ohio, that his friends say provided Obama with a steady equilibrium as he enters this final turn in the race for the White House. “As painful as the primary season was and how agitating it could be, it turned out to be a blessing for him,” said Eric Whitaker, an old Chicago friend who joined Obama aboard the crowded campaign plane. “But my role now is to keep him loose.”

The lines in Obama’s face have grown a bit deeper since he started his campaign, with the notches of grey hair along his temples far more pronounced.

He often carries the look of exhaustion, but flying the other night to Nevada, where he arrived after midnight, Obama passed on the chance to take a nap.

Instead, he walked around the cabin of his airplane, which is about the size of a bedroom, and talked about a favourite diversion, the coming basketball season. He took care not to step on a senior foreign policy adviser, Mark Lippert, who was asleep on the floor.

In the last days on the trail, he is finishing Ghost Wars: The Secret History of the CIA, Afghanistan and Bin Laden, and taking an occasional glance at US Weekly. He reads at least two newspapers a day and vigilantly checks his BlackBerry for updates on early voting tallies.

“In a marathon, when you are on mile 20 you start getting tired, but when you are on mile 25 you don’t,” said Lippert, who has grown familiar with Obama’s travel rhythms while accompanying him on the four foreign trips he has taken since becoming a senator. “That’s where he’s at.”

US VOTE GUIDE

How does theUS of A vote?

Americans don’t vote fora presidential candidate. They actually chooserepresentatives to theElectoral College, acomplex system in which voters in 50 states and the District of Columbia choose electors pledged to apresidential candidate

Who make up the Electoral College?

Each state is allocated a number of electors equal to the number of its Senators (always 2) plus the number of its members to the House of Representatives (which may change each decade according to the population). At present, a populous state like California has 55 electors while a state with fewer residents, like North Dakota, might have only three or four

How are the members chosen?

The political parties (orindependent candidates) in each state submit to the state’s chief election official a list of individuals as their candidates for electors and equal in number to the state’s electoral vote.Usually, these men and women are selected by the parties in their conventions. Members of Congress and government employees cannot become an elector

How does the college work?

On election day, voters cast their ballots for the party’s electors who represent their choice for President. Whichever party wins the popular votes in the state becomes the state’s electors, so that, in effect, whichever candidate gets the most popular votes in the state wins all the electors. Since there are 538 electors, a minimum of 270 is needed to win the electoral college

Is voting fully electronic?

No. Two-thirds of voters will mark their choice with a pencil on a paper ballot that is counted by an optical scanning machine. The rest will use electronic voting machines — similar to the ones in India — with no paper record to verify whether the choice was accurately recorded or touch-screen machines with paper trails

What are the likely pitfalls?

There have been complaints of shortage of ballot papers and voting machines, which are also prone to crashing. In case of touch-screen machines, there have been reports of malfunctions, ballot misprints causing scanners to jam and vote-flipping, in which the vote cast for one candidate is recorded for another. In Florida for example, touch-screen machines failed to record any choice for 18,000 voters during a House election in 2006

When will the results be known in case of a hitch-free election?

A definite conclusion can be made by 8am IST on Wednesday when results from North Carolina and Virginia are expected. Voting closes first in Virginia and North Carolina.If both these traditionally Republican states go for Obama, McCain is finished. On the other hand, if

Virginia goes into McCain’s column, it could be a long night in America. Officially voting closes on the West coast at 9.30am IST on Wednesday but all those in the queue as of closing time will be allowed to vote. So states like California and Washington will have the results possibly by 10.30am IST on Wednesday. But if it is a landslide for Obama, there will be no need to wait for those results

What happens next?

On the Monday following the second Wednesday of December, each state’s electors meet in their respective state capitals and cast their votes, one for president and one for vice-president

Can there be cross-voting?

Electors are expected to vote in accord with the popular vote. “Faithless electors” have occasionally cast their votes for a different candidate, but such protests have never influenced any election