Obama and Clinton near the finish line

emocratic presidential candidate and Senator Barack Obama (D-IL) speaks in Mitchell, South Dakota, yesterday.

emocratic presidential candidate and Senator Barack Obama (D-IL) speaks in Mitchell, South Dakota, yesterday.

Barack Obama and Hillary Clinton neared the finish line of their dramatic Democratic presidential duel on today, with Obama poised to claim the nomination as Clinton faces the possible end of her campaign.

Campaigning before the final two nominating contests in Montana and South Dakota, Obama promised to unify the party for the November election against Republican John McCain and said he and Clinton would be able to come together.

"Senator Clinton has run an outstanding race, she is an outstanding public servant, and she and I will be working together in November," Obama, an Illinois senator, said during a campaign stop in Troy, Michigan.

Clinton made a final campaign visit to South Dakota before she returns to New York tomorrow for a rally that could be her farewell to a race she entered as a heavy favorite but now has almost no chance of winning.

Obama is about 40 delegates shy of the 2,118 needed to clinch the win, and could reach the number quickly with help from some of the approximately 180 uncommitted superdelegates - party officials who can back any candidate.

Those superdelegates are expected to start announcing their endorsements once the voting ends in Montana and South Dakota, which have a combined 31 delegates at stake.

Voting ends in South Dakota at 7 p.m. MDT/9 p.m. EDT and in Montana at 8 p.m. MDT/10 p.m. EDT, with results expected shortly after.

In an e-mail fund-raising appeal sent to supporters, Clinton sounded like a candidate counting down the hours.

"I am so proud of the journey you and I have taken together, and of everything we have accomplished along the way. Tomorrow night, we'll count the final votes. Today, let's keep fighting," Clinton said.

Clinton's campaign is at least $20 million in debt, including more than $11 million she loaned it from her own pocket.

She scored an easy win over Obama in Puerto Rico's nominating contest on Sunday, giving fuel to her argument to superdelegates that she would be a stronger candidate against McCain.