Ex-Union leader and writer Jonathan Tasini qualified (by submitting a 40,000-signature petition) for the New York State primary ballot as the only challenger to Hillary Clinton in the September 2006 Democratic Party Primary for her current senate seat.
But the local television affiliate of Times Warner, NY1, which is broadcasting debates for every other NY-statewide Democratic primary contest, as well as the debate for the Republican Senate primary, refused to broadcast any debates involving Hillary Clinton and Jonathan Tasini. (Clinton, did however, appear in a "debate" without Tasini – and hence without any Democratic Primary rivals whatever.)
Why?
Tasini met all the criteria to participate in the debate (e.g. polling 13% in a Marist poll, above the 5% cutoff) except for raising $500,000. Tasini vs. Clinton was quite similar to the simultaneous Lamont vs. Lieberman senate primary race in neighboring Connecticut (which Lamont won) in all ways except that Lamont had a fortune estimated as between $90 and $300 million. That made Lamont "serious" and "worthy of media coverage" whereas Tasini was essentially entirely blocked out of all New York media and not allowed in any debate. In terms of the issues, the two races were very similar – the incumbent voted for the Iraq War while the challenger was antiwar, and the challenger considered that his central issue.
However, Hillary Clinton refused to mention the Iraq war in any of her campaign ads so far (late August 2006) – an attempt to avoid the issue which, thanks to Tasini's lack of wealth and the media's refusal to cover him, so far has been entirely successful.
NY1 appears to have set an arbitrary criterion of $500,000 with the sole purpose of excluding Tasini. (The previous year, NY1 had used $50,000. Tasini had raised about $150,000 at the time.) "Coincidentally," the Time Warner Political Action Committee gave $4000 in 2003, $1000 in 2004, and $5000 in 2005 to Friends of Hillary even though at those times, she had no election opponents whatever.