Dem. Sen. Murphy: Obama paid too little in taxes

"We can’t collect 18 percent from people making that much money and be able to afford to build roads and bridges and educate kids and do the medical research we used to,” Murphy told MSNBC's "Morning Joe."

"We just sort of need to make a fundamental admission that this nation can’t run on collecting 17 percent of GDP and that largely needs to come out of the pockets of the people making that kind of cash.”

Murphy added that "we can’t run this country based on the amount of revenue that we’re collecting today," and knocked the "mythology" by which the wealthy would be unwilling to invest or create jobs if they were taxed at a higher rate.

"The fact is that if a hedge fund manager is going to have to pay 5 or 10 percent more in income, it’s not going to change their decision-making and it’s not going to stop them from making risks," Murphy said. "They’re still going to make billions of dollars, even if they’re paying 20 or 25 percent. I think we have to step back and say that this mythology of people only investing money by getting a 15 percent tax rate just isn’t true.”

Tax returns released by the White House on Friday showed Obama reported income of $608,611 in 2012 and paid $112,214 in total taxes, good for an effective federal income tax rate of 18.4 percent. The first family donated $150,034 to 33 different charities, representing nearly a quarter of their gross income. 

In a statement from White House press secretary Jay Carney accompanying the release of the returns, the administration reiterated its call for a rule that would put a floor on the deductions the wealthiest Americans could take on their income taxes. Under the president's plan, no household making more than $1 million would pay less than a 30 percent income tax rate, with exceptions for charitable donations.

"The president believes we must reform our tax system which is why he has proposed policies like the Buffett Rule that would ask the wealthiest Americans to pay their fair share while protecting families making under $250,000 from seeing their taxes go up," Carney said. "Under the president’s own tax proposals, including limitations on the value of tax preferences for high-income households, he would pay more in taxes while ensuring we cut taxes for the middle class and those trying to get in it."