WASHINGTON (CNN) -- The U.S. Senate opened debate Monday on a sweeping bill to overhaul the nation's health care system.

Senate Majority Leader Harry Reid launched what is expected to be a lengthy and rancorous legislative battle by hailing the debate as one of the most important in U.S. history.

However, the process quickly bogged down in Republican procedural objections, causing Reid to lament: "This is not a good way to start this debate."

Republican Sen. Mike Enzi of Wyoming challenged a proposal by Reid that he said would unfairly cut off the proposal of amendments, including a planned Republican amendment that would prevent any cuts to the government-run Medicare health program for senior citizens.

Democrats contend the bill will ensure Medicare's future financial stability by eliminating waste and reducing costs. Reid said the bill "saves money, saves lives and saves Medicare."

Republicans contend that proposed Medicare cuts would harm senior citizens, with Sen. Jon Kyl of Arizona saying the bill "can't be fixed" if the Medicare provisions it contains remain intact.

The House has passed its version of a health care bill, and if the Senate eventually passes its bill, the two measures would be merged by a congressional conference committee. Both chambers then would have to approve the revised bill before it could go to President Barack Obama's desk.

The-CNN-Wire/Atlanta
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