"I really do think we're going to win back the House," Biden said Friday, speaking to House Democrats at their annual retreat in Cambridge, Md.
Biden said voters have tired of the GOP agenda, and the obstruction and inability of Washington to find compromise. Americans, he said, are beginning to "figure it out" that the White House policies are working to get the country back on track.
President Obama will be reelected, he said, and Pelosi will be remembered not only as the first woman speaker.
"She's going to be remembered as the second woman speaker," he said, as the Democratic lawmakers rose to applaud.
Democrats have been meeting for three days at the Hyatt here, discussing issues and strategies for the legislative and political agenda this election year.
Obama is scheduled to speak Friday afternoon.
Taking back the House remains an uphill climb for Democrats, who would need to net 25 seats to win the majority.
New polling this week shows voters now prefer a Democrat in Congress by a slight margin, but the political climate remains in flux as voters are dissatisfied with the dysfunction in Congress and continue to be worried about the economy.
Republicans held a similar get-away last week at a waterfront Marriott in Baltimore.