Sen. Tom Harkin, a veteran Democrat and a leading liberal voice, told CNN Monday that he and other Democrats may try to block the fiscal cliff deal that's being furiously negotiated ahead of the year-end deadline.
"They think Republicans may object? We may object," Harkin told CNN.
The Iowa Democrat said he and other progressives are furious about any suggestion of raising the household income threshold to $450,000 for tax cut extensions. President Barack Obama campaigned on a promise to raise rates on households making more than $250,000 a year.
Many Democrats objected to that higher threshold when briefed by their party's Senate leadership on Sunday, according to Harkin.
Harkin also added he is unhappy that Democrats are considering keeping some or all of the estate tax cut in place, and making the Alternative Minimum Tax patch permanent.
He said progressive senators will meet to discuss tactics Monday morning.
After speaking to CNN, Harkin took to the floor of the Senate with his objections to the deal currently being negotiated.
"If we are going to have some kind of a deal, the deal must be one that really does favor the middle class, the real middle class, those making 30, 50, 60, 70 thousand dollars a year. That's the real middle class in America," Harkin said. "As I see this thing developing, quite frankly, as I have said before no deal is better than a bad deal and this looks like a very bad deal the way this is shaping up."