Any compromise struck today to avert the "fiscal cliff" isn't going to completely please anyone. Evidence of potential political fault lines began surfacing early Monday as senators began responding to reports from overnight on the negotiations.

Sen. Tom Harkin (AP)

Speaking first after the Senate opened for a rare Dec. 31 session, Sen. Tom Harkin (D-Iowa) reacted angrily to reports in Monday's Washington Post that Vice President Biden was on the verge of striking a deal with Senate Minority Leader Mitch McConnell (R-Ky.) that would raise tax rates only on earnings of over $450,000 a year and permit a vote on the politically sensitive issue of the estate tax that would allow taxes on inherited estates to remain at their current low levels.

"This is one Democrat that doesn't agree with that at all," Harkin said. "What it looks like is it looks like all of the tax things are going to be made permanent, but all of the other things that the middle class in American depend on is extended for one year, maybe two years."

"If we're 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 that are making $50,000, $60,000, $70,000 a year," Harkin said later. "That's the real middle class in America. As I see this thing developing, quite frankly, as I've said before -- no deal is better than a bad deal. And this looks like a very bad deal the way this is shaping up."

When Harkin concluded, Sen. Barbara Boxer (D-Calif.) attempted to strike a more positive tone.

"I have listened carefully to my friend, Senator Harkin's remarks, which I would have to describe as fairly negative," she said.

"We all know that no side, if there is a deal, is going to get 100 percent of what they want," Boxer said later. "We know that because one party doesn't control everything."

In the absence of a deal reached today, Boxer said she would stand by her vote to approve a series of automatic federal spending cuts set to take affect Wednesday -- no matter the political consequences.

"I think we have to step up to the plate and admit that that's the policy we voted for," she said. "I'd much prefer to ease it, and I think there are ways to do that."

She suggested that money being spent on military operations in Iraq and Afghanistan could be put towards other government programs -- a familiar recommendation from liberal Democrats, but one that many Republicans call a budget gimmick.

Sen. Patrick Leahy (D-Vt.) made a similar suggestion after Boxer spoke, noting -- as many lawmakers regularly do -- that much of the nation's fiscal woes can be traced to spending on the wars in Iraq and Afghanistan.

"As one Vermonter said to me, you spend all this money to build these roads and bridges in Iraq and Afghanistan, and then they blow them up," Leahy said. "Why don't you rebuild our roads and bridges in America. We Americans will take care of them. So... with all the talk of where we are, let's not forget the big elephant in the room. That was two wars on a credit card, one going far longer than we had any reason to. The other one totally unnecessary in the first place."

"That was money that could have been spent in American for Americans to make America better," Leahy added later. "We wasted it there. Now we say how can we punish Americans, the average American? How can we punish them for the mistakes we made going into two wars. We'll punish them to pay for them. Come one, let's face up to reality."

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