PRINCETON, NJ -- A majority of Americans (54%) say Mitt Romney should release additional tax returns, while 37% say he should not, according to a USA Today/Gallup snapshot poll conducted Wednesday night. Predictably, Democrats strongly favor his releasing more tax returns, Republicans have the opposite view, and independents mirror the national tendency to favor Romney's releasing more returns.

While presumptive Republican presidential nominee Romney has released his 2010 tax return and has promised to release his full 2011 return when it is filed, he has balked at the idea that he release returns from previous years.

The Obama campaign has been pressuring Romney to release more tax returns, presumably because it would call further attention to the way in which Romney acquired and managed the wealth he developed as head of the private equity firm Bain Capital. Romney's years at Bain have become a centerpiece of the Obama campaign's criticisms of Romney in campaign ads, speeches, and media appearances.

While Americans favor Romney's releasing additional tax returns, they are divided as to whether doing so would damage him politically. A combined 44% believe the returns would damage Romney's campaign, with 29% saying they would show something harmful and 15% saying they would reveal something so serious it would show he is unfit to be president. Another 42% believe the tax returns would not reveal anything harmful to his campaign. Fourteen percent of Americans do not have an opinion on the matter.

Democrats are most likely to say the returns would reflect negatively on Romney, including a third who say they would reveal information that shows Romney is unfit to be president. Republicans are highly likely to say the returns will not reveal anything politically harmful. Few independents say the additional tax returns would reveal information showing that Romney is unfit to be president; the rest say the information in those returns either would be harmful to the campaign (36%) or would not reveal anything harmful (40%).

Americans are split when asked a general question concerning the importance of a presidential candidate's tax returns in providing voters with useful information to consider in their vote choice. Forty-seven percent say tax returns are largely irrelevant and 44% say they provide voters with legitimate information. Thus, a lower percentage of Americans say a candidate's tax returns provide useful voter information than say Romney should release additional returns. This no doubt reflects the tendency for Americans to react in a partisan way when actual candidates are involved. Still, Democrats generally view tax return information as important and Republicans claim it is largely irrelevant.

Implications

The long-term impact of Romney's decision about releasing multiple years of his tax returns is difficult to predict, but in the short term, not releasing his returns is out of sync with the majority opinion of Americans. The key players in this equation are independents, who by a 53% to 36% margin say Romney should release additional returns. Democrats and Republicans take the predictable stands on this issue dictated by partisan loyalty to Romney or to his critics -- although three in 10 Republicans say he should release more returns.

The Obama campaign, sensing a winning issue, will no doubt continue to criticize Romney for not releasing his returns and ask, as it has in campaign commercials, "What is Mitt Romney hiding?" Romney and his advisers will at the same time no doubt monitor the situation, balancing off the possible costs that come from releasing hundreds of additional pages of tax returns for his critics to pore over, against the benefits that would come from releasing the returns and appearing transparent.

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