Hillary Rodham Clinton has challenged rival Barack Obama to agree to new Democratic party primaries in Michigan and Florida. Clinton told supporters in Detroit that it is "wrong, and frankly un-American" for the two states to not have delegations to the national convention.
Obama has not yet said he favors or opposes the idea of a re-vote. His campaign has raised a number of questions about a plan in the works in Michigan for another primary in June.
The effort for a second primary in Florida collapsed last weekend.
Clinton trails Obama in delegates after primaries and caucuses in more than 40 states. Her chances of catching up to him are slim. But if the primaries are held again in both states and she wins lopsided victories, she could persuade more of the party's superdelegates to back her at the convention.