Kirk Dornbush says he's the "last person" who should be supporting Barrack Obama.

Dornbush, president of the Atlanta-based Iconic Therapeutics Inc., has a long history with the Democrats' power couple, Bill and Hillary Clinton. He raised cash for Bill in 1992. His dad, Terry Dornbush, was ambassador to the Netherlands during Clinton's presidency. In 2000, he backed John Edwards.

But this year, it's neither Clinton nor Edwards getting his support. It's Obama, the first-term senator from Illinois.

Obama, 46, is the youngest of any of the presidential candidates this year. He's spent less time in Washington than most, and he has the least extensive resume. Yet, he's been able to attract a who's who from Wall Street and the entertainment industry.

Among his backers: Paula Crown of Chicago's $4.1 billion Henry Crown family; Mark Gallogly, founder of Centerbridge Capital Partner; Penny Prtizker, chairman of ClassicResidence by Hyatt; Dreamworks cofounders Jeffrey Katzenberg and David Geffen; and Oprah Winfrey, who threw a huge Obama bash last month at her estate in Montecito, California.

Executives and Wall Street bankers who back Obama say they believe he can be just what he portrays himself to be—an agent of change who can reach across party lines to break through political gridlock. To them, that's more important than his lack of an M.B.A. from Harvard.

Alan Solomont, C.E.O. of health and eldercare company Solomont Bailis Ventures in Massachusetts and an Obama fundraiser, thinks the business sector sees in Obama the ability to anticipate the future. "The best business and political leaders are leaders who can lead transformational change," he says.

In a survey of 258 C.E.O.'s by Chief Executive magazine released in early August, Obama was called the best Democrat for American business, while Clinton was tapped as the worst. The war on terror far outweighed issues like fiscal and tax policy, health care, and energy, when asked which issues were most important to executives surveyed.

Obama's appeal is such that he has drawn support from some unlikely quarters, including Republicans like Bobby Stein, an investor in Jacksonville, Fla., who supported President Bush in 2004. Stein has hosted events for Obama and is on the candidate's list of "bundlers"—people who have raised more than $50,000 for his campaign.

His candidacy has also drawn some young people who were not engaged in politics at all until meeting him.

"We're seeing a whole new generation of people who have never raised money before or been involved in policy development take a shot at it," says Michael Froman, an informal Obama adviser who was a Harvard Law classmate and chief of staff to Clinton Treasury Secretary Robert Rubin.

Veteran Democratic fundraiser Bob Farmer, who served as national finance chairman for four presidential campaigns before signing on to the Obama camp, says younger business executives present a golden opportunity for Obama.

"This is a new campaign with a candidate who doesn't have a history of support around the country," Farmer says, "and this is an opportunity for them to get involved on a very significant level and become part of the Obama family. I think that's an attraction."