Michigan Governor Jennifer Granholm and Florida Governor Charlie Crist say it's "reprehensible" the voices of 5.2 million people who voted in the two primaries would be silenced.
Democratic Sen.won both contests in January.
They say it's "intolerable" that the Democratic National Committee has stripped the states of their delegates for moving up their primaries in violation of DNC rules.
DNC officials have suggested to both Michigan and Florida that holding another presidential contest of some kind would be one way to get the delegates seated. Both states say caucuses would be expensive to run.
CBS News senior political correspondent Jeff Greenfield reports that the Clinton campaign may be thinking about asking for "re-dos" in the two states.
"A do-over could change the whole complexion of this race," he said.
The DNC Credentials Committee could also agree this summer to seat the delegates.