The other day I lamented that the U.S. two-party system is suboptimal, and suggested that proportional voting might enable minority parties to have more influence, thereby enabling more innovation among candidates.

Be careful what you wish for!  I received an email from Ivan-Assen Ivanov, a Bulgarian, reporting that they have proportional representation, and it isn't working out:

Bulgaria is a prime example of the perils of proportional representation.

In our electoral system, the country is split into around 25 regions, and parties issue separate proportional lists for each of them.  The parliament seats assigned to each region are split among parties proportionally to their results in the region - more specifically, according to a procedure called Dont's method.  Any parties who get below 4% on a national level don't get represented, no matter how high their result in an individual region is.

What is the result of that?

We have currently three major political parties: the ex-communists, a pro-Western conservative party, and a populist centrist party which came out of nowhere three years ago.  And a small party, DPS, claiming to represent the Turkish minority, but hijacked by shady corporate interests.  Currently the DPS is in coalition with the populist party, but in all possible outcomes from the next elections, none of the three (or possibly four, since the pro-Western conservatives are on the verge of splitting in two) major parties will have majority, and the DPS will be the most likely candidate for a coalition.  Their participation in future governments is virtually guaranteed, and they're selling their position to the highest bidder.  (And they're using their ethnical origin to threaten with the spectre of ethnicol violence if they are eliminated from Bulgarian politics - after all, Kosovo and Bosnia are both within a day's drive from Sofia, the capital of Bulgaria.)

I understand that similar cases of overblown influence of fringe groups are common everywhere where there is no stable two-party system.  E.g. in Germany the Green party, which is ultra-left, some would say communist by their ideology, is the key to Chancelor's Schroeder stability - and they're pulling the entire government to the left and to their agenda, shutting down nuclear powerstations and holding violent "peace" demonstrations in front of US army bases.  (There's a joke in Europe about Green parties being like watermelons: green on the outside, red on the inside.)

So, I'll take your bipartisan system any day over the tyranny of small parties who've been lucky to be at the right place at the right moment :-)

So be it - nothing like real data!  I also received email from others pointing out that in Israel's system fringe parties have undue influence, with negative implications.  Fascinating.

So the downside of proportional representation is that small fringe parties have too much influence, while currently in the U.S. it could be argued they do not have enough.  I wonder if there is a middle ground?  Or perhaps every system has its upside and downside, and none is “best”.

Another aspect of this issue is whether it makes sense at all to have electors, or whether there should just be "direct" democracy.  A great issue for another post, stay tuned :)

P.S. It is SO awesome that I post one little entry on my blog here in California, and within hours I get informed emails with counterpoints from readers all over the world.  Absolutely amazing.