Sen. Ben Cardin said Wednesday he is optimistic that the supercommittee will fix the Sustainable Growth Rate formula.

“We have to start with a realistic budget baseline,” the Maryland Democrat told about 500 National Institutes of Health employees at a town hall meeting on the agency’s main campus in Bethesda, Md.

Repealing the SGR is estimated to cost about $350 billion over the next decade, but wouldn’t have to be offset to meet the supercommittee’s goal of $1.2 trillion if the Bowles-Simpson baseline is used, Cardin said.

Speaking with reporters after the meeting, Cardin also said he would oppose any effort to raise the Medicare retirement age, whether President Barack Obama endorses it in his speech next week or the supercommittee does later this year.

Instead, the Democrat, who sits on the budget and finance committees, said he hopes for a “grand bargain” of $2.7 trillion without further cuts to discretionary spending, such as the two-year pay freeze for federal employees agreed to earlier this year.

He said $1 trillion could come from bringing the troops back from the Middle East and closing tax loopholes for corporations and the wealthy.

Cardin also said he hopes the Congressional Budget Office will be more generous this fall in scoring savings from quality and efficiency measures in the Affordable Care Act.

Federal employees are under attack in the “partisan bickering” over the debt negotiations, he said, “but the federal workforce did not cause our budget problems.” Reassuring the NIH employees, Cardin said he hopes to shield them from further cuts.