Английский разговорный словарь (основной) - tactical adjective (politics)

Of voting: involving a switch of electoral allegiance for strategic purposes (especially so as to prevent a particular party or candidate from succeeding). Also of a voter: operating on this principle. Etymology: A specialized use of tactical; a person voting on this basis is using a tactic designed to ensure that the candidate he or she favours least is not elected. History and Usage: Voting designed to keep one's least favoured candidate out was first described as tactical in the mid seventies. The practice--and therefore also the name--became widespread in British general elections and (especially, perhaps) by-elections during the eighties. An elector living in a constituency where his or her favoured party has no hope of success is most likely to vote tactically, so as to confound the opposition. There was glee in Government quarters at Labour's predicament. Mr Rifkind, Scottish Secretary, said Labour had lost one of its safest seats and said Tory tactical voting had contributed to the swing to the SNP. Daily Telegraph 12 Nov. 1988, p. 1