President Barack Obama's re-electionteam made rival Mitt Romney a surprise offer on Friday: release five years worth of your private tax returns and we will stop talking about the other five.
The Republican's response? No -- but thanks for the note.
Obama's challenger, a multimillionaire former private equity baron, has been lambasted by Democrats for refusing to release a decade's worth of his personal tax returns from before 2010.
"Governor Romney apparently fears that the more he offers, the more our campaign will demand that he provide," Obama's campaign manager Jim Messina wrote in a letter to his counterpart, Matt Rhoades.
"So I am prepared to provide assurances on just that point," he promised.
"If the Governor will release five years of returns, I commit in turn that we will not criticize him for not releasing more -- neither in ads nor in other public communications or commentary for the rest of the campaign."
Rhoades rejected the offer in a casually worded email that began: "Hey Jim, thanks for the note."
"It is clear that President Obama wants nothing more than to talk about Governor Romney's tax returns instead of the issues that matter to voters, like putting Americans back to work, fixing the economy and reining in spending.
"If Governor Romney's tax returns are the core message of your campaign, there will be ample time for President Obama to discuss them over the next 81 days," he added.
Rhoades said Romney would lay out his plans for the public health insurance program for seniors known as Medicare, welfare and the "23 million Americans struggling to find work in the Obama economy."
The email was signed off with "See you in Denver," a reference to the first debate between the two contenders at the University of Denver on October 3.
Describing Obama's offer as "surely not unreasonable," Messina said a five-year disclosure would help the clear up outstanding questions about Romney's tax history, including the range in the effective rates he paid.
"Other presidential candidates have released more, including the governor's father who provided 12 years of returns," Messina noted. Romney's father George Romney unsuccessfully ran for president in 1968.
The release of Messina's letter comes a day after Romney offered his fullest explanation to date about his tax status, saying he paid at least 13 percent a year over the past decade, a much smaller proportion than most US wage-earners.
But Obama's campaign appeared less than impressed, demanding proof.
Romney paid an effective tax rate of 13.9 percent in 2010, according to returns he has released, as his income from investments was taxed as a capital gain rather than under the higher rates applied for salaried income.
Observers saw Messina's letter as a way to fuel the controversy and keep it in the headlines.
David Gregory, political journalist and moderator with broadcaster NBC, called the move "total gamesmanship, an opportunity to keep this alive."