* Conservatives demand harder stance to defund Obamacare
* House leadership aides: More time needed to explain plan
* Government shutdown looms at the end of September
WASHINGTON, Sept 11 A Republican plan aimed at averting a government shutdown in less than three weeks ran into a wall of opposition on Wednesday from conservatives in the U.S. House of Representatives, and leaders delayed any votes on it until at least next week.
The plan, derided as a "trick" by some conservatives, would have let them cast an essentially symbolic vote to defund "Obamacare" health reforms without risking a shutdown, feared by party leaders who remember the political damage they suffered when government offices shut their doors in the mid-1990s.
The move in the House of Representatives is the latest indication that a revolt by conservative Republicans is complicating Congress' efforts to deal with looming fiscal deadlines over government funding and the federal debt limit.
The delay pushes Congress closer to the Sept. 30 deadline for approving new government funding. With conservatives demanding a tougher stance on defunding and delaying President Barack Obama's signature healthcare legislation, known as "Obamacare," the chances of a shutdown appear greater.
The conflict is part of what is being called by some analysts a "civil war" within the Republican Party, energized in part by rallies and Tea Party gatherings during the August recess and the organizing efforts of the conservative Heritage Action, a sister to the conservative Heritage Foundation.
House Majority Leader Eric Cantor had previously scheduled a vote this week on a continuing resolution to fund the government for 11 weeks coupled with a measure to defund Obamacare before the law's health insurance exchanges launch on Oct. 1.
Conservatives, led by Representative Tom Graves of Georgia, were crafting an alternative plan that would combine the two elements, making it harder for the Democratic-controlled Senate to ignore Obamacare as it moves to fund the government. The alternative one-year plan would also include a year-long statutory delay for implementation of the law.
"I will not surrender in the fight to delay Obamacare for all Americans," said Representative Steve Scalise of Louisiana, who heads a large group of House conservatives called the Republican Study Committee. "We must use every legislative avenue available, through the CR, the debt ceiling, and sequester conversations to free the country from the President's train-wreck of a healthcare law."
Scalise and other conservatives said the Cantor plan lacked teeth and would ultimately allow for passage of a stop-gap spending bill, healthcare money and all.
Republicans say the healthcare law will hurt job creation, while supporters view it as a landmark initiative that will extend health insurance coverage to millions of Americans.
Moderate Republicans who supported the leadership plan said the hard-line stance that conservatives demanded would likely prompt a shutdown of the type that Republicans forced in 1995 and 1996 on then-President Bill Clinton - ultimately helping to seal the Democrat's re-election.
"I think there's a number of people who don't remember when the government was shut down the last time and who carried the burden of that? That was Republicans," said Representative Mike Simpson of Idaho, a member of the House Appropriations and Budget committees.
A House leadership aide said more time was needed to explain the plan to members and answer their questions, adding, "We are talking to people right now."
It would take only 16 Republicans to defect from the party's 233-member majority to sink the Cantor plan. Some 80 House members had signed a letter last month requesting that House Speaker John Boehner put forward a spending measure that defunds Obamacare.
A senior House Democratic aide said all 200 Democrats intended to oppose the defunding plan. Democrats also are opposed, the aide said, because the Republican funding measure would simply extend current discretionary spending levels of $988 billion annually, reflecting automatic, "sequester" across-the-board spending cuts.
Democrats favor higher spending levels and want to replace sequester cuts partly with tax increases on the wealthy.
Opposition to the Cantor plan has been fueled by conservative Tea Party activists and groups that see a denial of money as a last-ditch effort to prevent the healthcare law from taking full effect after some 40 previous House votes to repeal or curtail the law failed since its 2010 passage by Democrats.
The conservative group FreedomWorks on Tuesday blasted House Republican leaders in an Internet posting, saying their plan would ultimately support Democratic policies.
"Apparently House Republican leaders think we're stupid," wrote Dean Clancy, a FreedomWorks vice president, referring to Cantor's plan for moving the CR through the House. "It's a brazen betrayal."
A new poll released by the Pew Research Center illustrated the discontent within the Republican ranks. The survey found that only 27 percent of Tea Party Republicans and those leaning toward the Tea Party approved of their congressional Republican leaders' performance, while 71 percent disapproved.
But Senate Democrats have little problem with the Cantor plan, a senior Democratic aide said, because they can easily defeat the Obamacare provision and pass the spending measure.
The aide said a vote to support Obamacare funding would not be difficult for senators in tight 2014 re-election races because they voted to pass the reforms in 2010.
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