CHICAGO: US President Barack Obama warned supporters Sunday that he was no Usain Bolt, and that his re-election bid would be a fight all the way to the finish line, not an easy jog to victory.

Obama ushered well-heeled supporters into his Georgian-style mansion in Chicago's Hyde Park neighborhood for a rare glimpse of the home he left behind when he won the White House in 2008. He offered a pep talk to the crowd of around 100 of Chicago's elite, who had paid $40,000 a head for the exclusive invitation designed to swell his campaign coffers ahead of the presidential election on November 6.

The president predicted a tight struggle with Republican as he asks voters for a second term.

"This is not going to be a race like Usain Bolt where we're like 40 yards (meters) ahead and we can just kind of start jogging 10 feet (three meters) before the finish line," Obama said referencing the Jamaican legend, who has won the 100 meters and 200 meters sprint double at the last two Olympics.

"We're going to have to run through the tape. But we're really well positioned to not just win but to keep America moving forward."

The president stood against a backdrop of conifers and Christmas trees in the well-kept front yard of his three-story red brick mansion in an appearance that offered reporters an unprecedented close look at his home.