Rep. Connie Mack (R-Fla.), who is running for U.S. Senate, declined to say Tuesday whether he would extend the current interest rate on federal student loans, which will double on July 1 if Congress does not extend it.

MSNBC's Chuck Todd asked him where he stood on the issue on "The Daily Rundown."

"Well, look, again, I think what is happening in the state of Florida, if you don’t mind, Chuck, I want to talk about what’s happening here in the state of Florida," Mack replied.

Todd interjected: "No I understand that, but this is a vote you're going to have to make in Congress."

Mack went on, "Wait, wait, wait, but what I’m telling you in the state of Florida during this Senate campaign, people are concerned about their homes and jobs. That is the issue."

(Video below via MSNBC.)

After he finished, Todd said, "But you’ve got to cast a vote on this issue about student loans. What vote are you going to cast?"

"Well, we’ll take it -- when the vote comes up, we’ll cast that vote," replied Mack, continuing to talk about jobs and the deficit.

"You don’t think anybody is concerned about their student loan interest rates?" Todd asked again.

"We will absolutely be able to cast a vote, and when that happens we’ll be happy to do so," Mack said.

President Barack Obama is pushing for an extension of the 2007 law that halves interest rates on subsidized federal Stafford loans to 3.4 percent. He is speaking on the issue Tuesday at the University of North Carolina at Chapel Hill and the University of Colorado at Boulder. Presumptive GOP nominee Mitt Romney said on Monday that he agreed with the extension.

The possibility that rates will double comes as student loans recently surpassed credit cards as the largest amount of debt held by Americans.

The White House said that the potential hike would cost the average student $1,000, based on $4,200 borrowed per year and a 12-year repayment period. The Congressional Budget Office estimates that a one-year extension would cost $6 billion.

UPDATE: 2:22 p.m. -- The campaign for former Sen. George LeMieux (R-Fla.), Mack's rival for the Republican Party nomination, seized on Mack's refusal to take a position on the issue.

"Today, Connie Mack the Fourth showed he’s unable to properly answer a basic policy question, proving again he is unfit and unprepared to be a United States Senator,” spokeswoman Anna Nix said in a statement.

LeMieux added in the statement that letting student loan interest rates double would be "unconscionable."

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