Senate liberals are challenging GOP leaders on a proposed budget that would keep billions of dollars in ObamaCare savings while repealing the law.

Sen. Angus King (I-Maine) questioned Republicans for calling for a full repeal of ObamaCare while assuming the “same level of federal revenue” – which he said includes new dollars generated from the healthcare law’s reforms.

{mosads}“How can a budget engage in double counting of this kind?” King said during the budget committee markup Wednesday.

Sen. Sheldon Whitehouse (D-R.I.) also blasted Republicans for a budget that “leaves in a trillion dollars in ObamaCare revenues.”

“That seems to be an unusual combination,” Whitehouse said.

Sen. Mark Warner (D-Va.) reiterated that point later in the hours-long hearing.

The Senate’s budget blueprint, which was unveiled Wednesday, resembles a proposal put forward by the House Budget Committee on Tuesday. Like the Senate’s budget, this year’s House proposal would also keep some savings from ObamaCare, which would then be funneled into healthcare reforms, according to a GOP aide.

Whether to keep cuts made under ObamaCare has been a  controversial issue for Republican budget writers since the law’s passage.

In the last two years, Republican budgets did keep the roughly $700 billion in savings from Medicare while calling for a full repeal.

That approach differed from the budget proposed by 2012 GOP presidential nominee Mitt Romney, who pledged to repeal the cuts and restore the $716 billion in spending.

The GOP budget also cuts funding for entitlement programs like Medicare, Medicaid and the Children’s Health Insurance Program (CHIP), a move that Democrats also lambasted.