In any election, a voter may find several candidates acceptable while not feeling much of a special preference for any one of them. For this and other reasons, voters may be perfectly willing to compromise with other voters. But plurality voting fails to allow them any way to express such a willingness. Plurality voters have no alternative but to arbitrarily choose just one among the several to claim as their first-choice favorite; the voter is prevented from indicating anything more. Forcing such groundless but potentially important choices on voters surely marks plurality as an poor way to run elections. In comparison, with BAV voters can convey, with considerable precision, in what ways they are willing or unwilling to compromise with other voters.
In addition, BAV avoids a flaw that is common in other voting systems. BAV avoids penalizing candidates based on how famous they are. Curiously, such insidious favoritism typically benefits the most famous candidates (such as the nominees from the duopoly). Such tilting of the ground in favor of the famous is particularly pernicious because it is a bias that itself encourages a duopoly.
Still, some people do praise the two-party duopoly. Perhaps this is merely a reflection of believing duopoly to be inevitable. But these individuals are apt to note a concern that with more than two parties there would be gridlock. They note that it leaves no path for either party to force through its agenda. But we know that with duopoly, such gridlock is all too common; it is not mere conjecture.
But consider what a serious insult to democracy it is if one party is able to enforce its agenda against the wishes of a nearly equal number of others who steadfastly oppose that agenda. Democracy flourishes in the give and take of negotiation and compromise for resolving such a differences; it is wounded when compromise is replaced by an insensitive exercise of momentary power. There is reason to hope that by eliminating duopoly we will encourage more compromise and negotiation. And significantly, BAV would enables voters more power to influence the direction such negotiations take. Being free to choose from among more candidates will make voters more powerful and that will motivate their elected representatives to be more attentive to the needs of those voters.
Democratic politics can hope to realize its full potential only if it promotes lively competition and BAV promises a simple way to achieve that more lively competition. This is not to say that it will be easy to get BAV widely adopted. Still, Latvia has managed to overcome that challenge.
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