Hometown: Contested -- either Kabul or the Panjshir Valley
Key supporters: Tajiks
Background: A trained ophthalmologist, Abdullah is suave, at ease with the press, and speaks several languages, including English. Although running as an independent, Abdullah was the pick of the National United Front, a loose coalition of parties opposed to Karzai. He has a strong following in the north and in the provinces directly north of Kabul; as his popularity grows, so does the possibility of his tipping a swing vote away from Karzai.
Abdullah's greatest asset is his close association with the legendary commander Ahmad Shah Massoud, whose handsome, brooding face graces many of Abdullah's campaign posters. But Massoud, who was assassinated two days before the September 11 attacks, might prove to be just as much of a liability to his former spokesman. Called the Lion of the Panjshir, he is revered as a national hero by a large part of the population, but reviled by the Pashtuns -- who see him as no better than the rest of the warlords who tore the country apart during the civil war from 1992 to 1996.
Odds of winning: Slim, but growing