New Hampshire - President Barack Obama hounded Mitt Romney on Saturday, saying his wealthy rival would pay only 1% in taxes on his vast wealth under a plan authored by his running mate Paul Ryan.
Obama escalated his effort to use the pick of the conservative Republican congressman last week to drive votes away from Romney in swing states, including New Hampshire, where he was campaigning Saturday.
"The centerpiece of my opponent's entire economic plan is a new five-trillion-dollar tax cut, a lot of it going to the wealthiest Americans," Obama said.
"His new running mate, Congressman Ryan, he put forward a plan that would let governor Romney pay less than 1% in taxes each year, and here's the kicker - he expects you to pick up the tab."
The president is demanding that Romney, a former venture capitalist, release more than the two years of personal tax returns he has already promised, and paints his rival as the epitome of a society tilted toward the rich.
On Thursday, Romney insisted that he had always paid at least 13% in taxes, but that figure could still be politically damaging as it is much lower than the rate paid by most middle class Americans.
Romney, estimated to be worth around $250m, has his income taxed as investment earnings, rather than as an annual salary, hence the lower rate, complicating his campaign to deny Obama a second term on November 6.
In his budget proposal, Ryan would eliminate double taxation on interest, capital gains or dividends, reasoning that greater savings would lead to higher productivity and more investment.
Romney has however said he would keep taxes on capital gains, interests and dividends at the current rate, but eliminate them entirely for those earning less than $200 000 a year.
Obama cited a study by the bipartisan Tax Policy Centre that said that Romney's policies would result in middle class families paying an extra $2 000 a year, while the wealthiest Americans would get a big tax cut.
But the Romney campaign said that after the release of new figures showing a rise in the unemployment rates in 44 states, it was not surprising the president was launching another attack.
"The fact is President Obama wants to raise taxes on private investment and job creators, which will lead to higher unemployment and fewer jobs," said Romney campaign spokesman Ryan Williams.
"The Romney-Ryan plan eliminates taxes for the middle class on interest, dividends and capital gains and implements pro-growth policies to deliver more jobs and more take-home pay for middle-class families."
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