Updated

Senate lawmakers are close to a final vote, but not over the hurdle yet, for a prescription drug plan that requires at least 60 members' votes to pass.

The bill, which is designed to help low-income elderly and seniors with high drug costs to get Medicare benefits, is above the $300 billion limit put into previous budget outlays. Since it also has not gone through the committee process, the bill will require 60 votes to pass.

It is unclear if there are those 60 votes out there at this point, but lawmakers are scheduled on Wednesday to vote on setting an end to the debate.

The chamber is currently debating the prevailing drug proposal authored by Sens. Bob Graham, D-Fla., and Gordon Smith, R-Ore., which is estimated by the Congressional Budget Office to cost $395 billion over 10 years.

The compromise plan has been endorsed by the AARP, the nation's largest association for senior citizens, but Smith is the only Republican on board with the new plan.

"I don't think they have the votes and they shouldn't have the votes," said Sen. Charles Grassley, R-Iowa.

Democrats such as Sen. Edward Kennedy of Massachusetts, who had lobbied for a universal plan to offer benefits to all older Americans, have thrown their support behind the scaled-back measure.

"It's a significant down payment, which will help millions of senior citizens who need help the most and protect all senior citizens against catastrophic drug costs," Kennedy said Monday. Kennedy is chairman of the Senate's health committee.

Politically, the bill is a significant back down from Democratic plans for a $594 billion plan. It is also more than the $370 billion that Republicans want, but both parties fear that without any action, a massive attack and counter-attack will occur during the election season, something neither party can afford to lose points on.

Some GOP lawmakers had taken action to try to revise the Republican plan, which would be run by private insurers rather than the federal government, but that was rejected last week on a party line vote.

Grassley, Sen. Orrin Hatch, R-Utah, and other Republicans argue that, although it is less expensive than the measure offered by Democrats, their plan would offer at least some prescription drug benefits to all seniors. They have also offered to increase the sum to $400 billion to buy more drugs.

But Democrats are unwilling to back down on the issue of who will administer the plan, and insist Medicare take charge of the program.

The Graham-Smith plan would call for older people with incomes below 175 percent of the federal poverty level to get full drug coverage with nominal co-payments of around $1 to $3.

All others would receive government help of at least 5 percent of the cost of each prescription drug, with more government help available once a patient reaches $3,300 in drug costs. At that point, the person would pay a $10 co-payment on each prescription drug and the government would pay the remainder. There would be a $25 annual enrollment fee for the plan.

Fox News' Elizabeth Boswell and the Associated Press contributed to this report.