WASHINGTON - In a final drive to thwart President Barack Obama's health care remake, Republican senators plan to force Democrats to run a gantlet of politically dicey votes before they can finish a companion bill to the landmark law.

Voting was expected to start late Wednesday on a full list of Republican amendments to a "sidecar" bill making changes Democrats agreed to in the main legislation already signed by Obama.

Obama just signed the bill into law Tuesday, declaring it "a new season in America" at a celebrative White House ceremony. The main legislation would extend coverage to 32 million uninsured Americans over 10 years with a first-time requirement for nearly everyone to carry insurance and would ban insurance company practices such as denying coverage to sick people.

Approval of the "fix-it" bill at the end of this week is virtually assured, since it's being debated under fast-track budget rules that allow passage with a simple majority instead of the 60 votes usually required for action in the 100-seat Senate. Democrats control 59 Senate seats.

That didn't stop Republicans, who are unanimously opposed, from using the floor debate that began Tuesday afternoon as an opportunity to repeat the accusations they've lobbed at Obama's health legislation for the past year: that it raises taxes, slashes Medicare and includes a burdensome and constitutionally questionable requirement for nearly all Americans to carry health insurance.

Major components of the fix-it legislation include scaling back a tax on high-cost insurance plans opposed by labor unions, higher taxes on upper-income earners, and closing the coverage gap in prescription benefits in the existing Medicare government health care program for the elderly.

But Republicans have other ideas. Sen. Tom Coburn wants a vote on his amendment to prohibit coverage of Viagra for sex offenders. Sen. Judd Gregg wants savings from Medicare cuts plowed back into the health care program for seniors, instead of being used to expand coverage to the uninsured. Sen. Mike Enzi wants to gut penalties on employers whose workers wind up getting taxpayer subsidized coverage.

Democrats are vowing to bat down the Republican amendments one-by-one, and also hope Republicans won't succeed with any procedural objections.

"All of the amendments we'll take care of. Points of order - we'll see what they do," said Senate Majority Leader Harry Reid, a Democrat.

The main suspense surrounding this week's debate is whether the fix-it bill can emerge from the Senate unchanged. If it does, it can go straight to the president for his signature, since it's already passed the House of Representatives. If the Senate changes it even in a minor way, the legislation would have to go back to the House to be passed again, a prospect House leaders are prepared for but say they don't expect.

The fixes under consideration by the Senate were demanded by House Democrats as their price for passing the mammoth overhaul legislation that will extend coverage to 32 million uninsured Americans over the next decade.

"They're hoping that Americans don't notice this is another power grab," Republican Senator Jim DeMint said of Democrats. "So we're going to bring these issues up."

Although the battle may soon be over in Congress, opponents already have launched a campaign from the outside, with 13 state attorneys general, all but one Republican, suing Tuesday to overturn the legislation on grounds it is unconstitutional.

And Senate Republican leader Mitch McConnell served notice Tuesday of Republicans' continued campaign against the legislation ahead of the November congressional elections. "The slogan will be 'repeal and replace,' 'repeal and replace,'" McConnell said.

The president on Wednesday was to uphold his end of a deal reached with some moderate Democrats by signing an executive order affirming existing law against federal funding of abortions, except in cases of rape, incest or danger to the woman's life. The critical bloc of anti-abortion Democrats in the House had pledged to vote against the health care package unless given greater assurances that it would not amend current law.