But already some of Obama’s top financial backers are warning the White House: Raising money won’t be as easy this time around.

“They are getting organized in Chicago to start a massive two-year campaign, which I believe will be successful, but has extraordinarily large challenges in some of the major states,” said Philadelphia philanthropist Peter Buttenweiser, who hosted one of the first Obama presidential fundraisers in 2007 and is in talks to organize an early one for the re-election.

Obama’s team is running into resistance in at least one key fundraising hub — New York City, where some of Obama’s biggest 2008 backers have bitterly protested last year’s passage of financial reform legislation and what they perceived as an unfair bad-mouthing of bankers during the debate.

Obama was scheduled to go to New York this week to meet with about 25 large bundlers and supporters – and maybe clear the air – but that event was canceled after the Tucson shootings at the congressional event of Rep.Gabrielle Giffords (D-Ariz.), according to one prominent New York fundraiser.

In other places, such as Pennyslvania, top donors say Obama has to get in line behind other candidates who need the cash more urgently. And some donors are worried that the party has been slow off the mark in responding to the latest onslaught of GOP fundraising, millions of dollars raised from secret donors by a variety of Republican outside groups, including two associated with former Bush advisers Karl Rove and Ed Gillespie.

Wealthy donors and the Democratic operatives anxious to start up competing outside organizations that can blunt the Rove groups are growing frustrated as they await more specific direction from the Obama team about what form those efforts should take and who should lead them.

In interviews, several said two developments could quickly set things in motion: Creation of an outside group by an obvious Obama insider, or a major donation from a high level Obama supporter, such as Chicago fundraiser Penny Pritzker, to an existing group.

So far, neither of those things has occurred even as the GOP groups ready themselves for the race. “We are stumbling around,” said one Democratic fundraiser and activist.

To be sure, it’s early, and Obama and his team have proven to be prodigious fundraisers. In 2008, the president raised $745 million and became the first nominee in modern history to decline public funding and finance his campaign entirely with private money.

Simply duplicating that record-breaking sum would be a feat, particularly when Obama’s candidacy won’t be softly wrapped in the inspirational and historic themes of his first race, but he’ll run on an ambitious record of legislative accomplishments – victories that haven’t yet been embraced by his liberal base but have energized his Republican adversaries.