The morning after the election, the major candidates were neck and neck. It was clear that the result in Ohio, along with two other states who had still not declared (New Mexico and Iowa), would decide the winner. Bush had established a lead of around 130,000 votes but the Democrats pointed to provisional ballots that had yet to be counted, initially reported to number as high as 200,000. Bush had preliminary leads of less than 5% of the vote in only four states, but if Iowa, Nevada and New Mexico had all eventually gone to Kerry, a win for Bush in Ohio would have created a 269–269 tie in the Electoral College. The result of an electoral tie would cause the election to be decided in the House of Representatives with each state casting one vote, regardless of population. Such a scenario would almost certainly have resulted in a victory for Bush, as Republicans controlled more House delegations. Therefore, the outcome of the election hinged solely on the result in Ohio, regardless of the final totals elsewhere. In the afternoon Ohio's Secretary of State, Ken Blackwell, announced that it was statistically impossible for the Democrats to make up enough valid votes in the provisional ballots to win. At the time provisional ballots were reported as numbering 140,000 (and later estimated to be only 135,000). Faced with this announcement, John Kerry conceded defeat. Had Kerry won Ohio, he would have won the election despite losing the national popular vote by over 3 million votes, a complete reversal of the 2000 election when Bush won the presidency despite losing the popular vote to Al Gore by over 500,000 votes.

Why was there tension the day after the election?