Elizabeth Warren released the second television ad of her U.S. Senate campaign on Monday, linking her biography to some of the issues she has focused on in her campaign.

"I grew up in a family hanging on by our fingertips to a place in the middle class," says Warren, who is challenging Sen. Scott Brown (R-Mass.).

"But back then, America invested in kids like me. We had a lot of opportunities," she adds.

"Today, Washington lets big corporations like GE pay nothing -- zero -- in taxes while kids are left drowning in debt to get an education. This isn't about economics; it's about our values," Warren says in the ad.

Federal student loans could become more expensive if Congress does not act to renew a law keeping interest rates at 3.4 percent. Stafford loan rates are set to double on July 1 to 6.8 percent. President Barack Obama has pushed lawmakers to extend the current rates. Both Warren and Brown support the extension.

Presumptive GOP presidential nominee Mitt Romney also said he agrees with the extension to the law, which passed in 2007 with the support of 77 Republicans.