I do know that the League of Women Voters who used to run the debates withdrew in protest over the Repugs and Dems together raising the bar and essentially keeping third party candidates out of the debates.
on edit:
Google search:
PRESIDENTIAL DEBATES TO ENHANCE DEMOCRACY, NOT DUOPOLY
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... people." So said the League of Women Voters in explaining its 1988 decision to withdraw
from sponsoring the nationally televised presidential debates that it ...
reclaimdemocracy.org/pdf/ primers/citizens_debate_commission.pdf
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good commentary:
http://www.agrnews.org/issues/94/commentary.html
<snip>
The Presidential debates
The Presidential debates recently began operating under new management. Until 1984, the debates were sponsored by the League of Women Voters. The League withdrew its sponsorship because “the demands of the two campaign organizations would perpetuate a fraud on the American voter.”
Enter the Commission on Presidential Debates (CPD), operated by representatives from the two major political parties. The New York Times reported that the CPD was “not likely to look with favor on including third party candidates in the debates.”
The debates have become another avenue for the views of the major parties’ candidates. The CPD does not seem to count viewership as a high priority since when third party candidate Ross Perot participated in 1992, over 90 million people watched. In 1996, the debates between Clinton and Dole were only viewed by 41 million.
The exclusive, bipartisan control of the debates keeps third party candidates from gaining an audience. They are denied by the CPD as they are denied by the mainstream media. Their platforms and campaigns are further marginalized because they cannot gain access to the general public and therefore cannot illustrate how their views differ from the two major party candidates. The American voter is left to assume that there are only two voices worth hearing, and this is precisely the self-professed agenda of the CPD. “As a party chairman, it’s my responsibility to strengthen the two party system,” said Paul Kirk, a CPD official.
<snip>