* Conservatives lack votes to block fiscal measure
* Procedural vote set for Tuesday
* Final passage expected by Wednesday
By Thomas Ferraro
WASHINGTON, Dec 16 (Reuters) - Conservatives in the U.S. Senate are unlikely to stop passage of a two-year budget bill this week, with some Republicans expected to join Democrats in the Senate in voting for the measure.
Senate Republican Leader Mitch McConnell and a number of Tea Party-backed members, including Senators Ted Cruz of Texas, Marco Rubio of Florida and Rand Paul of Kentucky, are all likely to fight the deal, which was approved in a bipartisan vote of the U.S. House of Representatives last week.
But with other Senate Republicans declining to join them, for fear of sparking another government shutdown and distracting attention from the battle to discredit President Barack Obama's health care law, the opponents appear unlikely to have enough votes to erect procedural hurdles to the measure.
Backers of the deal are expected to muster the 60 votes needed in the 100-member Senate on Tuesday to overcome any blocking tactics and pave the way for passage of the White House-backed accord by Wednesday.
The measure would avert a government shutdown next month and possibly for the next two years. It would also ease automatic spending cuts, which many conservatives see as their only real victory in their battle to slash the U.S. deficit.
"The new budget deal moves in the wrong direction: It spends more, taxes more, and allows continued funding for Obamacare," said Cruz, who was a leading figure in the 16-day government shutdown earlier this year.
But other Senate conservatives appeared willing to go along, as did many of their allies in the House.
"Although I disagree with a number of provisions in the bill, on balance the good outweighs the bad," said Senator Ron Johnson of Wisconsin, a Tea Party favorite.
Utah Republican Senator Orrin Hatch, in a statement, said that while the deal "isn't everything I'd hoped it would be...sometimes the answer has to be yes."
Just weeks ago, a deal seemed out of reach for the sharply divided Congress, which has struggled to do much of anything the past three years and has consistently received a public approval rating of less than 10 percent.
But House Budget Committee Chairman Paul Ryan and Senate Budget Committee Chair Patty Murray reached an agreement last week, albeit a relatively modest one, that drew bipartisan support in Congress and words of praise from U.S. business leaders tired of fiscal uncertainty.
Ryan, among others, argued that holding out for larger cuts and possibly provoking another shutdown crisis would not only damage the Republican Party going into an election year, but draw attention away from the rocky rollout of the health care law, known as "Obamacare."
The Ryan-Murray pact does little to stem the growth of the $17 trillion federal debt, but it locks in spending levels for two fiscal years with the goal of eliminating the threat of another federal shutdown until at least Oct. 1, 2015.
REDUCES SEQUESTER CUTS
By allowing a $63 billion increase in spending on federal agencies and discretionary programs over two years in exchange for other budget savings, it also reduces across-the-board sequester cuts that have hit government programs from medical research to military weapons development.
Some Democrats are expected to vote no because the deal does not include an extension of jobless benefits for the long-term unemployed.
The Business Roundtable, an influential group representing leading U.S. companies, wrote senators on Monday urging them to support the deal and end their reckless fiscal ways.
(Additional reporting by Richard Cowan, David Lawder and Susan Cornwell; Editing by Fred Barbash, Cynthia Osterman and Peter Henderson)