But Ginsberg revealed the amount of carried interest in a conference call with reporters Tuesday morning. Romney earned $7.4 million in carried interest in 2010 and expects to earn $5.4 million in 2011.
The carried interest stems from Romney's ongoing interest in Bain Capital, the private equity firm Romney left in 1999.
Carried interest is controversial because some tax experts and lawmakers would like to have it taxed as ordinary income. Currently, it is taxed as a capital gain, which means gains are taxed at just 15 percent. Some say this unfairly benefits the managers of private equity funds and hedge funds, who often receive carried interest income.
Romney would have owed millions more in taxes if carried interest were taxed as ordinary income.
"Governor has not specifically talked about carried interest," a spokesman said on the call. Instead, he plans not to raise anyone's taxes but to work for a "fairer, flatter" tax code.
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