President Obama stressed taxes today in New Hampshire, arguing that Republican plans would serve only to reduce the tax bills of millionaires -- including GOP nominee Mitt Romney.

Romney running mate Paul Ryan "put forward a plan that would let Gov. Romney pay less than 1% in taxes each year," Obama told backers in Windham, N.H.

Obama attacked Romney on his proposed $5 trillion tax cut, saying it will have to be financed by raising other taxes or cutting programs that benefit the middle class.

The Republicans tried "this trickle-down snake oil" during the George W. Bush years, Obama said, but it led to the financial collapse of 2008 and recession. "It's not a plan to create jobs," he said. "It will not reduce the deficit, it will not move the economy forward, it's the wrong direction for America."

Obama made similar comments at a second rally today in Rochester, N.H.

The latest tax attack comes as the Obama team tries to pressure Romney into releasing more tax returns. Romney has refused, calling the issue a Democratic effort to distract attention from the bad economy.

His aides have disputed Obama's claim that Romney could pay less than 1% in taxes under GOP proposals. They said the Romney and Ryan plans keep the George W. Bush-era tax rates, while maintaining the capital gains tax rate. (At one time, Ryan did propose eliminating the capital gains tax, but it is not in his current plan, and Romney doesn't propose it either.)

The former businessman and governor of Massachusetts said this week he has always paid his fair share of taxes, at a rate of at least 13% per year.

Romney and aides note that Obama has proposed a tax increase by ending the Bush tax cuts for those making more than $250,000 a year. The Republicans say that plan will hurt job creators.

"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 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."

In New Hampshire, Obama noted he has cut taxes on the middle class, including the payroll tax.

The president also defended his Medicare policies, saying they will preserve the insurance program for the elderly, and the Romney-Ryan voucher plan will cost seniors thousands of dollars per year.

"On issue after issue, the choice could not be clearer," Obama said.