In advance of Tuesday's special election for the U.S. Senate seat in Massachusetts, the commonwealth has been carpeted with direct mail pieces depicting the Republican candidate as a "Wall Street insider" who "supports tax breaks for billionaires."

What has not been reported until now is that the negative mailings supporting the Democratic candidate were paid for by a political action committee funded by two New York billionaire hedge fund managers.

Campaigns often turn to direct mail for messages so nasty they don't want to put them up on television for everyone to see. In this case, however, the Senate Majority Pac has no shame — it's running a television commercial with the same "Wall Street insider," "loosen the rules on Wall Street bankers" language as the direct-mail pieces.

One glossy mailing asks, "Can we really trust Wall Street insider Gabriel Gomez to look out for Massachusetts families?" It claims, "Gomez became a millionaire while outsourcing American jobs" and "Gomez would cut Social Security to pay for tax breaks for the wealthy." Another mailing says, "Gomez is a Wall Street insider. He supports tax breaks for billionaires and wants to roll back consumer regulations and loosen the rules on Wall Street bankers while cutting programs that help the middle class."

This line of attack against Gomez is inaccurate because he's not actually a "Wall Street insider"; he lives in Massachusetts, and before becoming a candidate, he worked in the private equity business.

It's also foolish, because if "Wall Street" is code, as it often is, for attacking the financial industry overall, that industry, in the form of firms like Fidelity Investments, State Street, Wellington Management, and the Baupost Group, is a substantial positive contributor to the Massachusetts economy. Try selling municipal bonds for Massachusetts roads and bridges, or raising capital for growing technology companies in Massachusetts, without Wall Street.

Finally, it's hypocritical, because the same Senate Majority Pac that is attacking Gomez as a millionaire Wall Street insider was funded in 2011 and 2012 with $3 million from New York hedge fund manager James Simons and $450,000 from New York hedge fund manager David Shaw, Federal Election Commission records show.

Without naming Simons or Shaw or even New York hedge fund managers generally, the Boston Globe reported this month that the Senate Majority Pac is spending half a million dollars on advertising against Gomez. It also mentioned more than $342,000 in negative advertising against Gomez by a different political action committee backed by a California-based hedge-fund billionaire, Thomas Steyer.

The political action committee to which Simons and Shaw donated has ties to top Democratic politicians. Its co-chair, Susan McCue, served until 2006 as chief of staff to the Senate Majority Leader, Harry Reid. A member of the pac's board of directors, Julianna Smoot, was deputy campaign manager of President Obama's re-election campaign. And President Obama himself has set the tone of the pac's message with his own reference to "fat cat bankers on Wall Street."

When it's Republicans or libertarians like Sheldon Adelson or David and Charles Koch participating in the political process, the left-wing press works itself into a lather about the threat to democracy that is posed by the risk of "buying elections." Yet when it is James Simons or David Shaw paying for the attack ads, somehow no one seems to find it worth mentioning.

The hypocrisy and double standards don't stop there. If the Senate Majority Pac's smear campaign against Gomez succeeds, the Democrat who will take over the seat vacated by John Kerry will be Edward Markey, who was first elected to Congress nearly 37 years ago, in 1976. Then the Senate Majority Pac will move on to its next target, the Senate Republican Leader, Mitch McConnell. The pac says it plans a "30 years is too long" campaign criticizing McConnell's longevity in Washington.

If 30 years in the capital is too long for McConnell, why isn't 37 years too long for Markey? And if the Gomez-Markey Senate race is really about wealthy Wall Street insiders versus the middle class and Massachusetts families, why are the scare ads against the Republican candidate being funded by a political action committee backed by rich New York hedge fund managers? And, again, why are these independent expenditures considered so malignant when they are made by an Adelson or a Koch but not when they are made by a Simons or a Shaw?

These all would be fine questions for voters in Massachusetts and beyond to ponder on this Election Day.