In the Notional Republic of Zembla, the president is elected by a FirstPastThePost vote: the three main parties, the Nationalists, the Federalists and the Republicans, each put up a candidate, everyone votes for the one they like best, and the one with the most votes wins. In recent years, votes for the Republicans have waned, and so no Republican presidents have been elected. So, most Republican sympathisers have taken to voting for one of the other candidates: they reason that since they cannot hope to have a Republican president, they might as well try to exert some influence over whether the Nationalists or Federalists win. This is known as TacticalVoting.

TacticalVoting is a phenomenon which occurs under all voting systems (as demonstrated by the GibbardSatterthwaiteTheorem). It is A BadThing, not only because it means the votes cast do not reflect true public opinion, but because it can lead to a lock-in to two parties: in the above example, because the Republican vote collapses, it is likely that nobody will ever vote Republican again, unless there is major political upheaval.

The proposed 'solutions' are usually different voting systems.

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Anyone have research texts on Tactical Voting?

Probably not relevant, but you could try the StoneSociety.

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IMHO, TacticalVoting is rampant in the UnitedStates as well, because of a deeply instituted two-party system.  How many American citizens voted for one candidate simply to keep the other from getting in, as the lesser of two evils?  For me, usually the only way to avoid TacticalVoting is to write a candidate in, because I wouldn't trust either of the two major party candidates with my good silver.

--RobMandeville

What about other organized parties? The Green, Libertarian, Natural Law, Independent, American Independent, and Reform parties have public platforms and sometimes win local elections, making them better vehicles for dissent than write-in candidates who usually have negligible political impact.

''I think the point was not that there are no other parties, just that the other parties than the two have no hope because of TacticalVoting. IMO, the US political system is as deep in this as can be.'' -- PanuKalliokoski

''This is further complicated by the problem that the "two party system" is in practice a choice between two minorly differetiated centre-right parties.  The US is not the only one in this boat, although in theory the Canadian system should have more choice, in recent practice it is a one party show.''

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'''The Condorcet election method''' eliminates this problem through pairwise technology.

http://www.electionmethods.org/Condorcet.htm
(Note: This site calls Tactical voting Strategic Voting.)

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CategoryVoting