The U.S. Senate Tuesday failed to move forward on a bill to keep interest rates on federal student loans from doubling. The chamber, on a 52-45 party line vote, was not able to approve a deal to prevent a Republican filibuster to block consideration of the legislation, leaving the issue in limbo. The interest rate on federal student loans will double from 3.4 percent to 6.8 percent on July 1st unless Congress acts. Senate Democrats have proposed legislation to close corporate loopholes to pay for a $6 billion extension of low-interest federal student loans, The Hill said, but Republicans refuse to lift the threat of a filibuster. The Republican-majority House has approved legislation keeping the student loan interest rate at 3.4 percent, but Democrats reject it because it would cut funding for preventive healthcare.