The dominance of the two-party system in this country is rooted in the winner-takes-all set-up, in contrast to the parliamentarian proportional bullshit. Of course it is exacerbated by the way in which the presumption of two parties is built into the laws (e.g. in most states, the Democratic and Republican Parties’ primaries are publicly funded; the Libertarian Party’s primary is not; the pecking order in most legislative bodies is determined by the “majority” and “minority” leadership, rather than the “minority #1,” “minority #2,” “minority #3,” etc. leadership, or the members of the legislative body itself). And momentum.
The momentum is sort of an interesting phenomenon. 20% of registered voters will vote for the Democratic candidate nearly all of the time. And 20% will vote for the Republican candidate. Another 20% each will vote against the Democratic and Republican candidates. And because of a lack of imagination and viable alternatives, most of those votes go to the Republicans and Democrats, respectively. That leaves only one fifth of the voting public in the “independent” category. Which really only means that instead of nearly all of the time, only most of the time does party affiliation determine their vote. Or, to put it more accurately, the party to whom a candidate belongs is, for most independents, the default decisionmaking quality, but that the independent voter, unlike other voters, will actually look for other factors.
Is the two party dominance a problem? Probably. Any time a group of people get a leg up for silly, dated reasons, it leads to complacency, graft, and all-around bad feelings.
Solution? An easy one is to treat a candidate’s political party membership the same as you would his social organization membership. If a candidate is a member of the Eagles, Moose, or Rotary, he can tell everyone (I think), can get the organization itself to endorse him if it wishes. But it doesn’t have any impact on the ballot, by marking his name with a little “D” or “R,” by making his getting on the ballot easier than other candidates, or by getting his campaign paid for on a different basis than other candidates. And it doesn’t guarantee him plum legislative committee appointments should he be elected, or create an inevitable affinity that creates the dangerous temptation of mutual back-scratching.