Campaigns that made the outcome clear as mud

Shortly after 10pm on the evening of Thursday 29 July, with the ringing cry "I'm John Kerry, and I'm reporting for duty", the lanky, grizzled senator from Massachusetts strode onto the podium at the Fleet Centre arena in his home town of Boston to accept his party's presidential nomination. The closing phase of the 2004 US election campaign was under way.

Shortly after 10pm on the evening of Thursday 29 July, with the ringing cry "I'm John Kerry, and I'm reporting for duty", the lanky, grizzled senator from Massachusetts strode onto the podium at the Fleet Centre arena in his home town of Boston to accept his party's presidential nomination. The closing phase of the 2004 US election campaign was under way.

Since then, a passionate contest has fluctuated, leaving America and the world utterly uncertain if Mr Kerry or President Bush would prevail. At first, the edge went to the challenger after what was judged a successful convention - albeit one that laid more emphasis on the Democratic candidate's heroism in Vietnam than the contemporary wars against terrorism and in Iraq. But his advantage was less than met the eye. Hardly had the convention ended than a group of anti-Kerry Vietnam veterans took to the airwaves with their Swift Boat Veterans for Truth adverts, attacking Mr Kerry's war record. They dominated the front pages in August, their impact heightened by the mistaken initial decision of the Kerry camp to ignore them.

The Democrat clung to a narrow lead, but the Swift Boat veterans had softened him up perfectly for the Republican Convention to finish the job. That four-day gathering in New York was a festival of Kerry-bashing, depicting the senator as a "flip-flopper", incapable of defending the country. Mr Bush wrapped himself in the flag in a closing speech that was a smash hit and helped him open a double-digit advantage in the polls.

That lead shrank slightly, but September was a lousy month for Mr Kerry, unable to find a consistent message and incapable of galvanising the Democratic faithful, most notably the party's African-American constituency. Privately some Democrats were concluding their man would lose.

The debates, however, changed everything. In the first, on 30 September, Mr Kerry trounced a president who seemed peeved, testy and ill-informed (and, according to some, fitted out with a prompter concealed in his suit.) The Democrat won the two remaining debates as well, with his mastery of the facts and impressively presidential mien. By the time the final debate on 13 October was over, the race was a dead heat again - and still was as polls opened.

In the past three weeks, the candidates have focused on the "big three" swing states of Pennsylvania, Ohio and Florida, and the upper mid-western trio of Iowa, Minnesota and Wisconsin. Nationally, the President enjoyed a small lead, while the two candidates exchanged leads in the top battleground states.

In the final days, Mr Kerry relentlessly put Mr Bush on the defensive over the story of 380 tons of missing explosives in Iraq. Then came the Osama bin Laden videotape. The initial belief was that this would help Mr Bush by reminding voters of the terrorist threat. In fact, it seems not to have made the least difference.