WASHINGTON - On the eve of a House vote to repeal President Obama's health care overhaul, the administration has released a new analysis showing that up to 2.3 million Minnesotans could be denied health insurance due to pre-existing conditions if the law is overturned.

With Democrats forced to play defense on health care in the new Republican-led House, U.S. Health and Human Services Secretary Kathleen Sebelius released the report Tuesday with Gov. Mark Dayton as part of a nationwide mobilization over the vote, which is expected Wednesday.

Repeal has practically no chance of getting through the Senate, yet the vote has prompted a full-scale public relations battle, with skirmishes likely to play out state by state. "Repeal would be catastrophic for the citizens of our state," said Dayton, who is seeking to expand Medicaid for an additional 95,000 Minnesotans and extend the deadline to apply for a $1 million health-exchange grant, which Sebelius suggested is in the works.

While Sebelius termed the repeal "political theater," Republican leaders say the vote is the first shot in what will be a prolonged campaign leading up to the 2012 presidential election and beyond. And while Democrats have sought to tighten the focus on specific benefits of the 2010 legislation, Republicans have framed the debate in broader, ideological terms.

"We can improve health care without orchestrating a government takeover," said Minnesota Republican John Kline, chairman of the House Education and the Workforce Committee and a close ally of Speaker John Boehner.

Staking out turf

Officially termed "Repealing the Job-killing Health Care Law Act," the bill is expected to pass easily with the help of a handful of conservative Democrats and virtually the entire GOP majority, including all four Minnesota Republicans.

"To be honest, if I came out here and voted not to repeal ObamaCare, there'd be a lot of people scratching their heads asking, 'Why did we send you to Congress?'" said freshman Rep. Chip Cravaack, R-Minn. He made the health care bill the centerpiece of his surprise victory over veteran DFLer Jim Oberstar. "I'm doing what the people of Minnesota or the Eighth District sent me out here to do."

Minnesota Democrats seem equally eager to draw a line in the sand. "This is a chance to talk about it," said Rep. Keith Ellison. "We ought to be running to the House floor to talk about how good it is to fill the donut hole [Medicare drug coverage gap], and help young people trying to enter today's job market stay on their parents' health care."

Michele Bachmann, R-Minn., who sponsored the first major Tea Party rally against the health care bill at the Capitol more than a year ago, took part in a recall event Tuesday with several conservative allies, including Rep. Steve King, R-Iowa. "This is not what the American people bargained for -- spending more and getting less," Bachmann said.

She cited an analysis by Medicare's Office of the Actuary estimating that the new law could increase overall national health care spending by more than $311 billion over the next 10 years, in part because of increases in coverage.

Democrats have emphasized a Congressional Budget Office report estimating that repeal would drive up the federal deficit by $230 billion over the first decade, in part because the bill calls for large savings in Medicare payments to insurance companies.

"Now is not the time to step backwards," Rep. Tim Walz, D-Minn., said as the House began debate on Tuesday. "Folks in my district are already seeing the benefits of this new law. Seniors have received help paying for their prescription drugs and have better access to preventive care, saving money."

Pressuring Democrats

With frequent use of the pejorative "ObamaCare," GOP leaders hope to build momentum for dismantling if not repealing the expansive health care law, possibly by peeling off a few Democrats in the Senate who face election in two years. They also have targeted 13 of the 34 Democrats who voted "no" on the bill last spring and survived the midterm elections.

But at least one of them, Rep. Collin Peterson, D-Minn., has signaled that he has no intention of joining their effort. His spokeswoman, Allison Myhre, said that while he favors repealing parts of the bill that he considers costly or cumbersome, he views the GOP repeal bill a "political vote." One change that Peterson and many other Democrats agree on is the need to cut a provision of the 2,409-page health care law requiring companies to file 1099 tax forms for expenditures as small as $600 a year, which prompted concerns about an avalanche of paperwork.

Sen. Amy Klobuchar, D-Minn., cited the same provision Tuesday, saying that while the Senate will stave off a full-out repeal, there "could be very specific modifications to the bill."

Kevin Diaz is a correspondent in the Star Tribune Wash- ington Bureau.