CHICAGO (Reuters) - U.S. Democratic presidential candidate Barack Obama raised a record $66 million in August, a campaign spokesman said on Sunday.

US Democratic presidential nominee Senator Barack Obama (D-IL) speaks to the audience during a rally at Veterans Memorial Park in Manchester, New Hampshire, September 13, 2008. REUTERS/Neal Hamberg

The latest figures may bolster expectations of a money advantage that Obama could have over Republican candidate John McCain in the final two months before the November 4 election.

Opinion polls show that the race between Obama, an Illinois senator, and McCain, an Arizona Republican is dead even.

Obama spokesman Bill Burton said the August figure was helped by 500,000 new donors. The tally for the latest month exceeded the $55 million for February, which marked a record for Obama and an all-time high for any presidential candidate during a primary.

After far surpassing McCain in private fundraising, earlier this year Obama opted against taking public funds for the final stretch of the campaign.

McCain, who chose to take public financing, has access to an infusion of $84 million from a government presidential election fund for the period between the Republican convention and the November 4 election.

In August, his last month of private fundraising, McCain took in $47 million, a record for his campaign and a number that was helped by his announcement of his running mate, Alaska Gov. Sarah Palin.

Despite his prodigious private fundraising, Obama may not have as much of an advantage as he would when it comes to the amount of money he will have available to spend on advertisements and get-out-the vote efforts.

McCain benefits from money contributed to the coffers of the Republican National Committee, which has been more successful at raising money than the Democratic Party.

The need to raise money privately also means Obama needs to take more time off the trail to headline events with donors. On Tuesday, Obama is attending a glitzy Beverly Hills fundraiser that will include a performance by singer-actress Barbra Streisand, a long-time Democratic activist. That event could be one of the biggest Democratic fundraisers of the election cycle.

The Obama campaign said its cash on hand at the end of August was more than $77 million and that its total number of donors is now 2.5 million.