Members of Triple O, Obama's online operation, told The Washington Post in an exclusive breakdown that 3 million donors, in a total of 6.5 million donations, pledged more than $500 million as they ushered in a new digital era in presidential fundraising. The average online donation was $80.

Aides said Obama also raised millions from traditional campaign bundlers but the bulk came through the Internet.

His single biggest month of fundraising came in September when Obama amassed more than 65 percent of his record-shattering haul, $100 million of the $150 million total, from online donations, aides said.

Obama's e-mail list contains nearly 13 million addresses, aides told the Post. Over the course of the campaign, more than 7,000 messages were sent, many targeted to specific donation levels, and topping 1 billion e-mails in all.

One million people signed up for Obama's text-messaging program.