Anita Dunn, a Democratic pollster who has worked with Obama in the past, said the Illinois senator has tapped into a vast online resource that is fueling his ability to compete with Clinton.
"He has demonstrated a capacity to raise money from donors who aren't traditional Democratic party donors. That is extraordinary," Dunn said. "He appeals to younger voters who are much more comfortable giving money online."
However it isn't clear whether Obama's fundraising prowess will translate into votes in the Democratic primary and caucus contests in January in the early voting states of Iowa, New Hampshire, and South Carolina -- especially when it comes to younger voters, who are traditionally unreliable when it comes to turning out at the polls..
In the last fundraising quarter, Obama spent more than Clinton and as the early Democratic contests near, the candidates will spend even more money on advertising and campaigning.
"At some point you have to stop spending time with donors and start focusing on voters," said Massie Ritsch of the Center for Responsive Politics, a non-partisan organization that tracks candidates' fundraising and spending.
"The intense spending starts right now so you need to have a full bank account to do it," Ritsch said.
In a last push before the Sept. 30th reporting deadline, Clinton is holding fundraisers this week in New York and California.
"This is traditionally a tough quarter, but we're pleased with our level of support," Clinton spokesperson Blake Zeff said about the campaign's expected third quarter fundraising totals.
The Clinton campaign also recently gave a large chunk of money back to one generous political fundraiser, Norman Hsu, after the one-time fugitive was charged with fraud, and illegally making campaign contributions in the names of others.
"Losing $850,000 is a lot of money," admitted one Clinton campaign staffer, who suggested other candidates have had similar problems with donors.
On Monday, Obama took his fundraising pitch to Broadway for a theatre fundraiser that cost $250 to $2,300 per ticket.
Earlier this month, Obama got some financial help from talk show queen Oprah Winfrey, who hosted a star-studded fundraiser at her California estate for Obama, which raised a reported $3 million.
After contributions over the next week are included, the Obama campaign says it hopes to have a total of 500,000 donations from 350,000 donors at the quarter's end.
Republican strategists say the third quarter will be particularly important for the GOP candidates, who have thus far been out-fundraised by their Democratic counterparts.
Of particular interest will be how former Sen. Fred Thompson, R-Tenn., — the newest GOP candidate — will fare.
"It looks like Rudy Giuliani's going to lead this quarter, Mitt Romney's going to have to write another check to himself, John McCain is not going to break out like he was hoping he would, and Fred Thompson is going to be challenged, because he doesn't have a finance structure in place yet," predicted Scott Reed, a GOP consultant, who ran Bob Dole's 1996 presidential campaign.
Making what has become a frequent fundraising run through his homestate of Tennessee, Thompson is raising money in five Tennessee cities in two days this week.