On the Senate floor Monday morning, Sen. Tom Harkin, a liberal Democrat from Iowa, said he was “disturbed” to hear that Democratic negotiators had agreed to raise the threshold for the income tax rate increases to $450,000, from $250,000, and to maintain estate taxes at their current level.

“This is one Democrat that doesn’t agree with that — at all,” Harkin said. “I just think that’s grossly unfair.”