At least three sponsors have dropped their support of the 2012 presidential debates over the exclusion of third party candidate Gary Johnson.

While the Commission on Presidential Debates rules require that candidates must have at least 15 percent of the vote in national polls, Philips Electronics, the YWCA and British advertising firm BBH New York have all withdrawn their sponsorships over the exclusion of Johnson, the Libertarian Party presidential candidate.

Philips, the largest dropped sponsor thus far, said in a letter that the commission “may appear to support bi-partisan” rather than “non-partisan” politics.

Some libertarians reasonably point out that the commission apologized in 2002 for pulling Ralph Nader from a debate.

Cato Institute’s Gene Healy put it this way in his Washington Examiner column this week:

The “zinger” shootout tomorrow in Denver promises to be the same old stale, stage-managed affair. That’s the way the Demopublican duopoly wants it, and the Commission on Presidential Debates — the gatekeeper corporation set up by the two major parties in 1986 — makes sure the duopoly gets its way.