Democrats complained Friday that Gov. Mitt Romney boosted his federal income bill to fend off criticisms about the low tax-rate owed on income earned from investments.

“Romney manipulated one of the only two years of tax returns he’s seen fit to show the American people — and then only to ‘conform’ with his public statements,” said a statement from Sen Harry Reid, the leader of the Democratic majority in the Senate.

“Had he not limited his [charitable] deductions … what would Gov. Romney’s effective tax rate have been?” asked an afternoon email from Obama’s campaign staff.

In 2011, Romney choose to deduct from his taxable income only $2.2 million of the $4 million he donated to charity. By limiting that deduction, he increased his own federal tax rate to 14.1 percent, and deflated Democratic allegations that he paid little or no taxes in some years.

Obama’s chief campaign strategist, David Axelrod, complained that Romney would have paid only a 9 percent federal income tax rate if he had fully used his eligible charitable tax deductions. “Mitt’s 9 percent solution. Or, maybe, solution to 9 percent,” he tweeted Friday afternoon.

Romney may also have paid extra taxes in previous years, the Obama email suggested. “Gov. Romney has stated he did not pay less than [a] 13% tax rate in previous years. Did he have to revise other returns to get to that rate? … Has Gov. Romney voluntarily given up the use of certain charitable deductions before?” the email asked.

It is “galling to see the creative accounting Mitt Romney applied to his own tax returns. … It’s obvious he believes in two sets of rules: one for him, and one for the middle class,” said Reid, who has repeatedly claimed that Romney paid no taxes in some years.

The campaign’s questions were part of an email that sought to portray Romney and his tax-return announcements as deceptive.

The email asked a series of questions about taxes Romney might owe to overseas governments, the impact of a Romney-owned corporation in Bermuda, the value of a trust established by Bain Capital when Romney left the firm, and his accounting firm’s trustworthiness.

The email also argued that Romney paid a far lower tax rate than average Americans.

“Does Gov. Romney think it is appropriate that his income tax rate would be reduced under his tax plan, even though he paid less than the typical middle-class family?” the email jabbed.

Romney, however, paid far more in taxes — both as a dollar total and as an income percentage — than average.

“A family of four in the exact middle of the income spectrum will pay only 5.6 percent of its 2011 income in federal income taxes,” said an April 2012 statement by the Tax Policy Center. That’s down from 8 percent before the tax cuts championed by George W. Bush in 2001, said the report.

The center is run by the Urban Institute and Brookings Institution; the Obama campaign has repeatedly cited its research.

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