CHICAGO (Reuters) - Democratic presidential candidate Barack Obama’s fundraising machine rolls on with a record $66 million in August and 500,000 new donors added to the ranks, 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

Obama was running even or slightly behind his Republican rival John McCain in opinion polls but led him in the fundraising race through the summer.

Obama has decided not to take public funds for the final two months leading up to the November 4 election so will need to spend some of that time raising cash. McCain is taking public financing so will receive $84 million from a government presidential election fund.

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 the Illinois senator and an all-time high for any presidential candidate during a primary.

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.

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

Obama took the day off from the campaign trail and stayed at home in Chicago. The night before, he canceled an appearance on NBC’s “Saturday Night Live” because he did not want to be making jokes while Hurricane Ike was ravishing Texas this weekend.

McCain was campaigning in the northern swing state of New Hampshire where he attended a NASCAR race, a sport usually more associated with Republican strongholds in the South. He toured the garage area and shook hands with the drivers.

“It’s great to be back in New Hampshire,” McCain told the race crowd. McCain’s win in the New Hampshire primary gave a boost to his campaign in January and got him back on track for the nomination.

He was to join up again this week with Palin, who has swelled crowds and brought enthusiasm to rallies when she appear with McCain.

They separated last week so that Palin could conduct her first media interview since her surprise pick for the No. 2 spot and some campaigning on her own.

Palin was the subject on Sunday of stories in The New York Times and The Washington Post looking into her record as mayor of Wasilla, Alaska, and governor of the state. The stories portrayed her as an executive who valued secrecy and loyalty and took disagreements very personally.

“Throughout her political career, she has pursued vendettas, fired officials who crossed her and sometimes blurred the line between government and personal grievance,” the Times said based on public documents and 60 interviews.

The newspapers said her style left some with bad feelings and she had appointed many of her school chums to major government posts. The Times said she appointed a high school classmate to a $95,000-a-year job at the State Division of Agriculture after she cited her childhood love of cows as a qualification for the job.

“When you defeat an incumbent mayor, defeat an incumbent Republican governor and then defeat a former Democrat governor and sign major ethics reform in a state with a number of corrupt politicians, you make some enemies but the end-product is government reform,” said Meg Stapleton, a spokeswoman for the McCain-Palin campaign.