After Senate Republicans blocked a Democratic bill Tuesday to preserve low interest rates on federally subsidized Stafford loans, Minnesota's two Democratic senators said they won't stop pushing for a solution.

"The bill the Senate failed to pass today would have helped these students with that challenge. I'm very disappointed that the bill failed but I'm not giving up. I'm going to continue to work with my colleagues on both sides of the aisle until we can figure out a way to prevent interest rates on federal student loans from doubling," said U.S. Sen. Al Franken.

The Democratic bill Franken and U.S. Sen. Amy Klobuchar backed would keep interest rates for subsidized Stafford loans at 3.4 percent for another year, rather than allowing the rate to double for new loans starting July 1. The rate on current loans would remain the same.

Republicans opposed the Democratic plan, which would pay to keep rates low by forcing high-earning stockholders in some small, privately-owned corporations and professional practices to pay additional Social Security and Medicare taxes. Democrats, including Franken, criticized the tax loophole.

"It's a loophole I don't think anyone can defend," Franken said Tuesday.

In the U.S. House, most Democrats rejected the Republican bill that would gut a preventative health program created by President Obama's Affordable Care Act. But the bill passed.

Both sides know they can't push through a student loan bill through Congress without bipartisan consensus on how to pay for it. That's what happened in 2007 when a law approved by a Democratic Congress, supported by Republicans and signed by then-President George W. Bush, gradually lowered the rates.

Now, without Congressional action, the rates will revert to 6.8 percent in July because lawmakers were worried about the costs even back then, but had to deliver on a campaign promise.

At a time when neither party wants to be blamed for letting students' grow larger in the middle of a congressional and presidential election year, the concerns about cost have to come to fruition. The Congressional Budget Offices estimates it will cost $6 billion to extend the rate for a single year, but both President Obama and presumptive Republican presidential nominee Mitt Romney have said they support keeping the rates low.

In hopes of winning support for the "Stop the Student Loan Interest Rate Hick Act," Klobuchar and Franken gave floor speeches back-to-back Tuesday.

"I urge my colleagues to take action and pass this legislation to block the rate hike and ensure college remains affordable for students in Minnesota and across the country so we can stay competitive in the global economy. Now is the time to come together and do what's right for our students and our country," Klobuchar said.

The Associated Press contributed to this report