DUBLIN (Reuters) - Ireland's biggest bookmaker Paddy Power said Thursday it would pay out early more than 1 million euros ($1.35 million) on bets that Barack Obama will be the next U.S. president, three weeks ahead of the election.

The Dublin-based bookmaker said it made the "unprecedented decision" to pay on bets taken so far, following Wednesday's final campaign debate between Obama and his Republican rival John McCain, which polls judged the Democrat to have won.

"We declare this race well and truly over and congratulate all those who backed Obama," Power said.

"Although he seemed a little out of sorts in last night's final debate we believe he has done more than enough to get him across the line on November 4."

The bookmaker said the overall betting trend had shown "one- way traffic" for the Illinois senator since the start of the summer, with odds shortening to 1-9, meaning a bet of 9 euros is required to make 1 euro profit.

Power said it had taken more than 10,000 bets on the 2008 U.S. presidential election, the majority in support of Obama.

In June a wager of 100,000 euros was placed on Obama to win at odds of 1-2, yielding a payout of 150,000 euros, it added.

(Reporting by Kevin Smith; editing by Andrew Roche)