US television news teams that sent election-night viewers to bed without a sure winner in the last two presidential races now face what many political pundits expect to be a swifter outcome next Tuesday.

With Barack Obama consistently leading pre-election opinion polls, network news executives are ready for the possibility that the Democratic nominee could emerge early in the evening clearly headed for victory over Republican rival John McCain.

If, as widely predicted, Obama captures such critical states as Virginia, Florida, Ohio and Indiana, where polls close by 8 pm Eastern time or earlier, experts say he would be well on his way to winning the White House before the Western half of the country finishes casting ballots.