Why are "third parties" given no airtime by the media?

With more and more people growing dissatisfied with both the Republican and Democratic parties, the statement I hear more and more often is “if only a third party candidate had a chance, I've vote for them.” But we all know that none of the third parties are showcased in the media. They're generally ignored and when they're actually mentioned, they are discredited.

I understand why the media only focuses on the primary elections of the two major parties. Since primaries are internal elections to pick candidates, they don't have much significance to those outside of a particular party. As such, it make sense that the media wouldn't give much attention to the primaries of the parties that aren't popular – they don't have many members, so their primaries will only be relevant for a small number of people. Since coverage of the primary process is mostly done simply because people are interested (rather than because it's newsworthy), it follows that the media would only focus on the primary elections that the most people care about.

But once the primary process is over, and the actual election campaign begins, the media still doesn't focus on any of the “third party” candidates. They're almost never invited to the debates, and none of their fundraisers or events are covered. This makes no sense to me. Any candidate running for President of the United States automatically becomes relevant to everyone in the country, and is most certainly a newsworthy topic. Yet these candidates are almost totally ignored.

When you think about it, the marginalization of these parties has even migrated to common speech – any party other than the Republicans or Democrats is automatically grouped into the blanket “third party” term. Apparently, these parties don't even deserve to be called by their actual names...

I follow the news and politics very closely, and I have almost no knowledge of any of the “third party” candidates, or their positions on the issues. What I do know I had to actively seek out. That's insane. How is it that the mainstream media, who supposedly champions free speech and fairness could ignore people running for the most important political position in the nation?

What's even more insane is that there are probably many politicians that cling to one of the two major parties simply because they fear becoming seen as irrelevant if they join forces with other more like minded people in one of the other parties. While watching the news earlier tonight, I saw a story on Ron Paul and his views. The reporter posed the question of why Paul remains in the Republican party, when many of his fundamental views are polar opposites with the rest of the party. While I haven't heard Ron Paul answer such a question directly, the answer seems pretty obvious to me: if he switched parties, no news program would be running a story on him. Even as the last place candidate with a very small number of supporters (relative to the other Republican candidates, that is), he still gets a certain amount of attention simply because he is running on the Republican ticket.

After the primary process is over, I'll be making a point to showcase the various candidates from each of the lesser known political parties. Be sure to check back often, as I report what no one else seems interested enough to even mention...