President George W Bush cast his vote, at 8.30 EDT, at a fire station in Crawford, Texas, and is now en route to Washington, DC, where he will now mark time, monitoring the results as they begin coming in, late this evening, from the White House.

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His main challenger, Democratic Senator John F Kerry, who started his day with campaign events in Wisconsin, voted at the State House in Boston, Massachusetts, at about 1 ET.

He will now join his wife, Teresa Heinz Kerry -- who voted in a Pennsylvania church -- and friends in a trip to his favorite restaurant in Boston, where he will have what he calls his lucky bowl of clam chowder -- a ritual he has rigorously followed in every election he has fought.

Meanwhile, across the country, reports speak of long lines of anxious, eager forming since early morning.

Bush and Kerry have both during their campaign emphasised that this could be the most important election America has faced in its history -- and judging by the lines forming, it appears citizens are eager to have their say. Click here for information on poll timings across the country).

A key area is California, which has 55 Electoral College votes (for info on the EC, and its role in US elections, click here -- and here, for an FAQ on the subject)  at stake. All polls indicate that Kerry is marginally ahead in the state, but that it is too close to call.

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In this key state, reports say that as early as 6 am, various voting stations reported over 100 people standing in line, waiting for the poll process to begin.

California has not, traditionally, been a state that registers high polling -– in 2000, for instance, only 44 per cent of the voters cast their ballot.

A community activist who is volunteering for a 'get out the vote' initiative in the state indicates in email that poll officials say such long lines, this early in the day, are unprecedented.

Similar reports are coming in from across the country, with even places of normally tepid polling showing signs of unprecedented activity. Washington, DC –- which in 2000 registered the highest winning margin for defeated Democratic candidate Al Gore, who polled 76.2 per cent of the votes cast -– has boasted lines wending around a city block and more, well ahead of the start of polling.

Projections are that the country could set a polling record this year, with estimates indicating that as many as 120 million, maybe more, may cast their votes.