President Obama is pushing Congress to raise taxes on millionaires again, hoping to gain support for the so-called "Buffett Rule."
The Buffett Rule is named for billionaire investor Warren Buffett, whose income is derived largely from his investments. The president says wealthy investors should not pay taxes at a lower rate than middle class wage earners.
Currently, capital gains and dividends are taxed at a top rate of 15 percent, while wages are taxed at as much as 35 percent. The Buffett Rule would raise the tax rate for millionaires to a minimum of 30 percent.
The push comes ahead of a Senate vote next week and has little chance of passing Congress.
Still, the Obama team is using the Buffett Rule as part of its attack on GOP frontrunner Mitt Romney, who has been criticized by Democrats for paying taxes at the 15 percent rate on his income, which is derived from investments.
"Romney is a beneficiary of a broken tax system, and he wants to keep it that way," Obama campaign manager Jim Messina said Monday, during a conference call with reporters.
Romney opposes the Buffett Rule, saying it amounts to raising taxes on small business. His campaign spokeswoman Gail Gitcho said Obama was the "first president in history to openly campaign for re-election on a platform of higher taxes."
Republicans point out that Obama's proposal would only bring in $47 billion through 2022, compared to federal deficits expected to hit $7 trillion during those years.