Biden to seniors: Romney will tax your Social Security benefits

(CBS News) BOCA RATON, Fla. - Vice President Joe Biden told senior citizens here Friday that Republican nominee Mitt Romney's economic plan could raise taxes on their Social Security benefits.

"Instead of dealing with a balanced approach, how to keep these programs in place, they've decided what you do is you shift all the costs to the recipients," Biden said to over 800 seniors.

He said most seniors don't have to pay taxes on their Social Security benefits and millions more pay taxes on only a fraction of their benefits. If Romney's tax plan goes into effect, he said, "the average senior would have to pay $460 more in taxes on their benefits."

Biden was extrapolating from studies that found Romney could not reach his goals of cutting taxes 20 percent for everyone and balancing the budget without ending or limiting some tax breaks that benefit the middle class. The assumption is that some of that tax burden would fall on Social Security benefits.

Romney has been unwilling to specify what deductions he would seek to eliminate, which leaves room for the Obama campaign to speculate about the impact on Social Security beneficiaries. But Romney has never said that he would raise taxes on Social Security benefits, and he has promised that he will not reduce Social Security benefits for current retirees.

Campaigning Friday in Wayne, Pa., Romney said it is President Obama who would raise taxes. "I don't want to raise taxes on the American people, not when our economy's in the kind of trouble it's in," he said. "I will not raise taxes on middle income Americans."

Sarah Huisenga and Margot Sanger-Katz contributed to this report.