A U.S. Senate bill to extend aid to states, unemployment benefits and a host of tax provisions appears likely to fail today, potentially blowing an $850 million hole in Gov. Ed Rendell's budget.

At a Washington news conference this afternoon, Senate Democratic leaders said they do not have assurances that their latest version of the American Jobs and Closing Tax Loopholes Act will garner the needed 60 votes for cloture today. Senate Majority Leader Harry Reid, D-Nev., said if the vote fails, he will move onto another bill rather than continue to revise a measure Senate leaders have tinkered with for weeks.

The House of Representatives passed a version of the bill that did not include the state aid sought by Mr. Rendell and other governors, an extension of Medicaid reimbursements that originated in the stimulus bill. If the Senate passes nothing at all, it would throw Pennsylvania's budget into additional turmoil.

Mr. Rendell was one of many governors who already included the Medicaid reimbursements in their fiscal 2011 budgets. The 6.2 percent reimbursement already had been extended through the end of 2010, but states had been counting on it through the first six months of 2011.

Mr. Rendell has lobbied aggressively for the extension, including a trip to Washington last month. Today in Harrisburg, he warned of 20,000 layoffs of state, county and municipal workers -- including teachers -- if the $850 million in federal help does not come through.

Three legislative caucuses have come to agreement on an overall general fund spending number of $28.2 billion, but Senate Republicans say that's too much and that the proposal is irresponsible because it assumes the state will receive the funds, known as FMAP.

House and Senate Democrats say states including Pennsylvania frequently pass budgets that anticipate federal funds that have not yet been approved.

Senate Republican spokesman Erik Arneson said that's true, "but this is different because it's an extraordinarily large amount of money being debated in D.C. with the prospects of approval growing dimmer each day."

Mr. Rendell said it would be "Armageddon" if the funding doesn't come through. "We'd be back to ground zero" in budget negotiations, he said.

Minority Appropriations Chairman William Adolph, R-Delaware, said that behind closed doors the governor's optimism for the funding is waning.

"The governor, for the first time since we've been talking, was not optimistic we'd be getting that money," he said after a closed-door negotiating session this afternoon.

House Speaker Keith McCall, D-Carbon, said there are contingency plans on the table in case the money doesn't come. He declined to specify what those plans are.

Though the U.S. House did not include the FMAP funding in its tax extenders bill passed last month, Senate Democrats had insisted on keeping it. But Republicans, and centrists Ben Nelson, D-Neb., and Joe Lieberman, I-Conn., balked at the additional spending. Mr. Nelson and Mr. Lieberman, along with a united Republican caucus, voted against cloture on a previous version of the bill.

Wednesday night, Democrats emerged with a cheaper piece of legislation that included a scaled-back FMAP reimbursement to save $8 billion. All of the spending was paid for, except the cost of extending unemployment benefits -- which Democrats insisted is crucial emergency spending. Republicans still appear unwilling to budge.

"Last night Senate Democrats introduced their latest version of the deficit extenders bill," Minority Leader Mitch McConnell, R-Ky., said in a floor speech this morning. "It has one thing in common with every other version they've offered: It adds new taxes and over $30 billion to an already staggering $13 trillion national debt -- despite consistent bipartisan rejection of that idea."

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