Barack Obama is expected to raise $100 million in June.

Leading Democratic fundraisers predict that Sen. Barack Obama (D-Ill.) will raise hundreds of millions of dollars over the next few months if he opts out of public financing and begins raising money for the general election.

Specifically, they say Obama could raise $100 million in June and could attract 2.5 million to 3 million new donors to his campaign.

These fundraisers say Obama could increase his fundraising dramatically because of three factors: a boost of enthusiasm among Obama donors following his clinching of the nomination; the migration of Sen. Hillary Rodham Clinton’s (D-N.Y.) donors to his camp; and the mobilization of big Democratic donors who have given little so far this year.

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