I am not posting this by any means to discourage anyone from voting their conscience but rather to perhaps enlighten some as to why the chances of a third party actually winning is slim to none if not nearly impossible.
excerpts from the book "Third Parties in America"
by Steven J. Rosenstone, Roy L. Behr, Edward H. Lazarus
Princeton University Press, 1984, paper
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To UNDERSTAND the significance of a third party vote, one must first recognize how difficult an act it is to undertake. A host of barriers, disadvantages, and strategies block the path of would-be third party supporters. So formidable are these hurdles that third party voting occurs only under the most extreme conditions... third parties will never be on equal footing with the two major parties and help explain why a third party vote signifies something very different from a vote for either the Democrats or Republicans.
The two major parties, in Schattschneider's words, "monopolize power" (1942, p. 68). They are able to do so via three routes. First, barriers-powerful constitutional, legal, and administrative provisions-bias the electoral system against minor party challenges and discourage candidates and voters from abandoning the major parties. Third party movements are further handicapped because they have fewer resources, suffer from poorer press coverage, usually run weaker, less qualified candidates, and do not share the legitimacy of the major parties.
Citizens do not accord minor party candidates the same status as the Democratic and Republican nominees; they see third party challengers as standing outside the American two-party system. These handicaps, by and large a side effect of the way the electoral system is set up, raise the cost of third party voting. A third party vote, therefore, does not merely signify the selection of one of three equally attractive options; it is an extraordinary act that requires the voter to reject explicitly the major parties......BARRIERS
The rules that govern elections in the United States are far from neutral. They form barriers that block the emergence and discourage the growth of more than two parties. These biases help ensure that the Democrats and Republicans retain their position of dominance. The founding fathers created some of these barriers; the two major parties have helped erect others.
CONSTITUTIONAL BIAS
The Electoral College system is particularly harsh in its discrimination against nationally based third parties that fall short of a popular vote plurality in every state. John Anderson, for instance, did not capture a single electoral vote in 1980, though he polled 6.6 percent of the popular vote. The Electoral College does favor regionally based third party candidates who are strong enough in particular states to gain pluralities. For example, in 1948, States' Rights nominee Strom Thurmond obtained 7.3 percent of the Electoral College vote with only 2.4 percent of the national popular vote.
Contrary to popular belief, most current proposals for eliminating the Electoral College would not benefit third parties. The most widely supported plan calls for the direct popular election of the president with a runoff if no candidate receives 40 percent of the votes cast. But as long as a president can be elected with less than an absolute majority of the popular vote, the plan would, for all practical purposes, work like a single-member-district plurality system. To prevent either the Democrats or Republicans from collecting 40 percent of the vote, minor parties would obviously have to poll at least 20 percent. This has happened only three times since 1840. Any direct vote system that allows a party to win with less than a full majority of the popular vote would hinder third parties, though the larger the plurality required to elect a president, the lower the barrier becomes....
...BALLOT ACCESS RESTRICTIONS
The Democrats and Republicans have constructed a maze of cumbersome regulations and procedures that make it difficult for minor parties and independent candidates to gain a spot on the general election ballot. Whereas major party candidates automatically appear on the ballot, third parties must petition state election officials to be listed. A candidate whose name does not appear is obviously disadvantaged: voters are not cued when they enter the polling booth; it is difficult and at times embarrassing for a voter to cast a write-in ballot...
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Because the states determine their own ballot access laws, minor party candidates wishing to place their names before the voters must overcome fifty-one different sets of bureaucratic hurdles. This is an arduous task for third party contenders, even well-financed ones. Petitions must be circulated within a specific time period that varies from state to state. They can be distributed only between early June and early August in California, for instance, and between August 1 and September 1 in Indiana. Filing deadlines also vary by state, and many occur relatively early in the election cycle-before the major parties have held their conventions....
...CAMPAIGN FINANCE LAWS
The 1974 Federal Election Campaign Act (FECA) is the most recent instance of the major parties adopting a "reform" that freezes out third party challengers. Under the law, the Federal Elections Commission (FEC) provides the major party presidential nominees a lump sum ($29.4 million in 1980) for their campaigns. On top of this, the Democratic and Republican National Committees can raise and spend as much as they need to pay for legal and accounting expenses incurred in complying with the act. State and local party committees can raise and spend an unlimited amount on voter registration, get-out-the-vote drives, and other volunteer activities. "Independent" committees can also spend freely on behalf of the major parties.
Third parties, on the other hand, are eligible to receive public funds only after the November election, and then only if they appear on the ballot in at least ten states and obtain at least 5 percent of the national popular vote. The exact amount a candidate receives increases with his total vote (assuming the initial ten state provision is met). Given these requirements, only 10 of the 148 minor party candidates (7 percent) that have emerged in more than one state since 1840 would have qualified for retroactive public financing. Although third party candidates are denied the benefits of the pre-election subsidy, they must still comply with the FECA rules on disclosure of campaign contributions and are bound by the ceilings of $1,000 per election from individuals and $5,000 from political action committees...
The list of disadvantages that a 3rd party experiences goes on -- full article:
http://www.thirdworldtraveler.com/Political_Reform/Third_Parties_America.html