Harkin said he will attempt to use special budget rules that only require a simple majority vote to advance a bill that would end the Federal Family Education Loan program, which would free up money for other education programs.

But centrist Democrats are blanching at Harkin’s move to use the reconciliation process for an education bill that includes major policy reforms, echoing concerns they raised over using those rules for healthcare legislation.

It's unclear whether the bill has even the 51 votes it would need to advance under reconciliation. While the legislation has strong backing from the Obama administration, which predicts that it could save the government more than $87 billion over 10 years, Republicans oppose it and enough centrist Democrats have yet to get on board. The bill has already passed the House on a largely party-line vote.