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Unveiling a new zinger against his opponent, President Obama tonight said Mitt Romney's tax plan amounts to "Robin Hood in reverse" because it would take money from the poor to help the rich.

"It's Romney Hood," the president said to uproarious laughter and applause from about 500 supporters who paid $500 each to attend a fundraiser in Stamford, Conn.

The president pointed to a recent study by the Tax Policy Center that found Romney's economic plan would raise taxes on the majority of Americans to give tax breaks to the super wealthy, a study that the Romney campaign has called "a joke" and "biased."

"The entire centerpiece of Mitt Romney's economic plan is a new $5 trillion tax cut," Obama explained. "Governor Romney's plan would effectively raise taxes on middle-class families with children by an average of $2,000 to pay for this tax cut, not to reduce the deficit, not to invest in things that grow our economy. … He'd ask the middle class to pay more taxes so that he could give another $250,000 tax cut to people making more than $3 million a year."

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Obama went on to say that the Romney campaign has been performing "all kinds of different gymnastics" to try and sell this "trickle-down, tax-cut fairy dust."

"And guess what?" he asked the rowdy crowd. "It doesn't work. … It's not a plan to create jobs, it's not a plan to reduce our deficit, and it is not a plan to move our economy forward."

The new line of attack comes as the president faces increasing Republican criticism for the flailing economic recovery.

"President Obama recently said the biggest regret of his first term was not telling better stories," Romney campaign spokesman Ryan Williams said in response to Obama's remarks. "He's trying to make up for it now, but his stories just aren't true. There's only one candidate in this race who's going to raise taxes on the American people, and that's Barack Obama.

"While he's used taxpayer dollars to grow government and reward his donors, middle-class Americans have seen fewer jobs, lower incomes, and less hope for the future. Mitt Romney has a plan for a stronger middle class, and, unlike President Obama, a record of accomplishment behind it."