As most people know, there are two dominant political parties in the United States: the Democrats and the Republicans. Third parties have not done very well at the national level in quite some time. No third party candidate has won a single electoral vote in the presidential election since George Wallace's American Independent Party won 46 electoral votes in 1968.

At the same time, third parties have not sat idly by over those 40 years. The presence of third parties has arguably affected several elections in recent memory. Ross Perot won nearly 19 percent of the popular vote in 1992 and then won 8 percent in 1996. Ralph Nader captured 2.7 percent of the vote in 2000, the closest election since 1876.

To many in the two big parties, third parties are at best a distraction and at worst thieves. Many Democrats blame Nader for taking away votes that would likely have gone to Al Gore had Nader not been in the race.

Some may wonder, "What's the big fuss over third parties? What's wrong with our two-party system?" One problem that I see in having just two parties nominate candidates is that it is difficult for someone to be elected who has an ideology that does not fit conveniently into one of the two parties' platforms. Such a candidate may hold positions that are popular with most voters but because some of their positions will upset this or that special interest group in one of the two parties, they'll never get nominated and will be forced to run as a third party candidate.

If you're a candidate running outside of the traditional two-party system, you have a tremendous amount of work to do to get your name on the ballot, get into the televised debates, etc. Even if most voters would prefer to have you over the other candidates, if they view you as a long-shot they will select the lesser of two evils to prevent the candidate they strongly dislike from winning. What ends up happening is that the second most preferred candidate is elected.

There is a solution to this problem. It involves having voters rank the candidates in order of preference instead of having them vote for just one. This kind of voting is known as "instant-runoff voting" and is used to elect the president in Ireland, members of Parliament in Australia and the mayor in San Francisco. The way it works is that voters mark their preferred candidate in first place, their second favorite candidate in second place and so on.

The election workers, or computers, then examine the ballots to see who the voters selected as their first choice. If one candidate has more than 50 percent of the vote, that candidate is declared the winner. If not, we take the candidate that received the fewest votes and eliminate him or her. The voters who voted for that candidate will then have their votes transferred to the candidate they ranked in second place. The process of eliminating the worst performing candidate from the previous round and then transferring his or her votes to the next preferred candidate on those voters' ballots is repeated until one candidate has more than 50 percent of the vote. This is called instant runoff voting because it simulates an election with many rounds of voting but done all at once.

The advantage of this system is that it produces a winner whose views more closely match those of the electorate. There is no longer any worry of "throwing your vote away" for a loser or compromising your principles by voting for a candidate you don't like. Under instant-runoff voting, you can vote for your favorite candidate while still having a say on who wins a contest between the major parties if your first choice comes in third place or worse.

Instant-runoff voting has made significant strides in recent years, and not just among third parties. In 2002, John McCain announced his support for instant-runoff voting for statewide elections in Alaska. That same year, then Illinois State Senator Barack Obama introduced a bill to implement instant-runoff voting in congressional and state primary elections. If this trend continues, instant-runoff voting may become a reality in the not-too-distant future.