After being lashed by the American Medical Association over the break, many GOP Senators that were targeted for their vote against the Medicare bill are standing firm in their opposition to House-passed bill.

Senate Majority Leader Harry Reid (D-Nev.) plans to press ahead with the Medicare vote on Wednesday. The Senate is not holding votes today as many lawmakers are attending the funeral of their former colleague, Sen. Jesse Helms (R-N.C.).

And signaling a fight with the same foes, Reid emphatically ruled out opening the amendment process Tuesday afternoon, telling reporters that such a move would bounce the legislation back to the House and “waste time.” Additionally, the Majority Leader said that if the cloture vote on the bill does not succeed, then the fault lies with Republicans.

Sen. John Cornyn (Texas), one of many Republican lawmakers who was targeted by AMA advertisements, said that he is unlikely to switch his vote for the Medicare bill. Cornyn, vice chairman of the Senate Republican Conference, appeared unfazed and a bit irritated by the outside political pressure to change his vote.

“I plan to do what’s right in spite of those advertisements and the rescinding of the endorsements,” Cornyn said, referring to the AMA media blitz as well as the Texas Medical Association withdrawing its endorsement of the Texas Republican.

Many Republicans complain that Reid is forcing them to swallow a partisan bill. Senate Republicans point to a purported compromise on the Medicare issue hammered out between Finance Chairman Sens. Max Baucus (D-Mont.) and ranking member Chuck Grassley (R-Iowa) as a reason to go back to the table and reach some sort of agreement.

However, some GOPers contend that if Reid would open up the amendment process, allowing some changes to the bill, then the way forward would be cleared.

Both Cornyn and Sen. Arlen Specter (Pa.), who was rumored to be the single GOP Senator that wrestled with his decision in voting against the measure, said they might change their votes if allowed to offer amendments.

Democrats, on the other hand, believe that their bill, which overwhelmingly passed the House, is the only option for their GOP colleagues and are not giving up on a plan to vote on the measure Wednesday.