"It's the first time that I feel it's more likely that we will go over the cliff than not," Senator Joe Lieberman, an independent from Connecticut, said on CNN's "State of the Union."

"If we allow that to happen it will be the most colossal consequential act of congressional irresponsibility in a long time, maybe ever in American history."

"It looks like to me that obviously this is going to drag on into next year, which is going to hurt our economy," Republican Senator Bob Corker of Tennessee said on CBS "Capitol Gains."

The Democratic president and Republican House of Representatives Speaker John Boehner, the two key negotiators, are not talking and are out of town for the Christmas holidays. Congress is in recess, and will have only a few days next week to act before January 1.

On the Sunday TV talk shows, no one signaled a change of position that could form the basis for a short-term fix, despite a suggestion from Obama on Friday that he would favor one.

The focus was shifting instead to the days following January 1 when the lowered tax rates dating back to President George W. Bush's administration will have expired, presenting Congress with a redefined and more welcome task that involves only cutting taxes, not raising them.

"I believe we are," going over the cliff, Republican Senator John Barrasso of Wyoming said on Fox News Sunday. "I think the president is eager to go over the cliff for political purposes. I think he sees a political victory at the bottom of the cliff."

Some Republicans have said Obama would welcome the fiscal cliff's tax increases and defense cuts, as well as the chance to blame Republicans for rejecting deal. Obama has rejected that assertion.

Democrats have charged that Boehner has his own self-interested reasons for avoiding a deal before January 3, when the House elected on November 6, is sworn in and casts votes for a new speaker.

Democratic Senator Charles Schumer of New York said on NBC's "Meet the Press" that Boehner has been reluctant to reach across the political aisle for fear it could cost him the speakership when he runs for re-election. "I know he's worried," said Schumer.

Boehner, who so far has no serious challenger for the job of speaker, has said that he has no such concerns.

Such finger pointing has been under way since Congress returned after the election, but it has gained intensity in the past few days, with the heightened prospect of plunging off the cliff.

Congress started the clock ticking in August of 2011 on the cliff. The threat of about $600 billion of spending cuts and tax increases was intended to shock the Democratic-led White House and Senate and the Republican-led House into bridging their many differences to approve a plan to bring tax relief to most Americans and curb runaway federal spending.

Economists say the harsh tax increases and budget cuts from the fiscal cliff could thrust the world's largest economy back into a recession, unless Congress acts quickly to ease the economic blow.

MARKETS COULD TUMBLE

The most immediate impact could come in financial markets, which have been relatively calm in recent weeks as Republicans and Democrats bickered, but could tumble without prospects for a deal.

Markets will be open for a half-day on Christmas Eve, when Congress will not be in session, and will be closed on Tuesday for Christmas.

Wall Street will resume regular stock trading on Wednesday, but volume is expected to be light throughout the week with scores of market participants away on a holiday break.

If Congress fails to reach any agreement, income tax rates will go up on just about everyone on January 1. Unemployment benefits, which Democrats had hoped to extend as part of a deal, will expire for many as well.

In the first week of January, Congress could scramble and get a quick deal on taxes and the $109 billion in automatic spending cuts for 2013 that most lawmakers want to avoid.

Once tax rates go up on January 1, it could be easier to keep those higher rates on wealthier taxpayers while reducing them for middle- and lower-income taxpayers. Lawmakers would not have to cast votes to raise taxes.

Some lawmakers expressed guarded hope that a short-term deal on deficit reduction could be reached in the next week or so, with a longer, more permanent deal hammered out next year.

But a short-term deal would need bipartisan support, as Obama has said he would veto a bill that does not raise taxes on the wealthiest Americans.

Democratic Senator Kent Conrad, chairman of the Budget Committee, said Obama and Boehner are not that far apart and that both sides should keep pushing for a long-term big deal.

"I would hope we would have one last attempt here to do what everyone knows needs to be done, which is the larger plan that really does stabilize the debt and get us moving in the right direction," Conrad of North Dakota told Fox News Sunday.

But most Republicans are now looking past January 1 to what they consider their next best chance of leveraging Obama for more cuts in the Federal budget - a fight over the debt ceiling expected in late January or early February. At that time, the administration will need Congress' authorization to raise the limit on the amount of money the government can borrow.

"That's where the real chance for change occurs, at the debt-ceiling debate," Republican Senator Lindsey Graham of South Carolina said on "Meet the Press."

(Reporting by Thomas Ferraro and Richard Cowan; Editing by Fred Barbash and Vicki Allen)

• A Permanent Economic Emergency