The same campaign advisers that have counseled Mitt Romney not to release several years’ worth of tax returns are counseling Sen. Scott Brown, who is running for re-election in Massachusetts, to do just the opposite.

Brown’s campaign plans to release six years’ worth of the Massachusetts Republican’s tax returns at the end of the week, the Boston Globe reported Tuesday.

And Brown’s campaign manager has penned a letter to Democrat Elizabeth Warren urging her to do the same.

“You have offered to release far more limited information, and even then have made that contingent on a demand that Senator Brown go first,” Brown’s campaign manager, Jim Barnett, wrote in the letter to Warren. “The people of Massachusetts deserve better from their candidates for Senate than the type of political gamesmanship you are engaging in.”

But Romney – who shares in common with Brown a top adviser, GOP strategist Eric Fehrnstrom – has repeatedly declined to release several years of tax returns despite having made available more than two decades’ worth of returns to Sen. John McCain’s (R-Ariz.) presidential campaign when he was being vetted as a potential running mate.

Earlier this month, Romney released his 2010 tax returns, and his campaign has said it will release its 2011 return before the November election. His advisers have maintained that the release of two years’ worth of returns is sufficient for a presidential candidate.

The Globe’s Matt Viser delves deeper into the tax return issue. Might it be a headache for Romney on the trail? Let us know your thoughts in the comments section below.