Historically it has been difficult to persuade many people to vote tactically. There is some of evidence that at the last election there was a little more tactical voting in some places and there may be more this time, but according to MORI only 11 per cent of people are currently considering voting tactically.
Bill Bush, the BBC's political analyst, points out that in 1983 the SDP Liberal Alliance won 26 per cent of the vote but only 4 per cent of the seats. It was intelligent tactical voting in some areas that secured the Liberal Democrats nearly as many seats in 1992 with only 18 per cent of the vote.
People have become a little more aware of the importance of where they vote in trying to secure the least worst outcome. But without proportional respresentation it is often a pretty vain effort.
The 1983 general election produced a monstrously unjust result, when the SDP Liberal Alliance gained only 1.5 per cent fewer votes than Labour yet massively fewer seats. Mrs Thatcher was re-elected, like every government since the war, with a minority of the vote and the will of the people was in no way represented in the Commons.
In its miserable aftermath, a gallant band of we failed Alliance candidates set out on a campaign to collect signatures on a petition to change the voting system, knocking on doors and explaining the virtues of PR. It was an illuminating experience.
Very few people understood that their vote was only counted locally. In some vague unspecified way they assumed their vote had been cast for the government of their choice. There was an underlying belief that somehow, somewhere, their vote for Maggie, the two Davids or Michael Foot had counted for something.
Of course in the great majority of constituencies, as ever it had counted for nothing, either piling up in absurdly wasteful majorities or lost in hopeless minorities. Once it was explained most people signed the petition eagerly. Once they understood, they were indignant and they wanted their vote to count for more.
As for tactical voting, it is often deeply confusing for already muddled voters. In every constituency, the two losing parties both pretend that only they can beat the incumbent. If, say, it is a solid Tory seat, both Labour and Lib Dems will pepper the voters with leaflets claiming that they are the only ones able to oust the sitting MP.
The Lib Dems will point out that they came an easy second last time, and if only the Labour voters would all switch to them, they could win. Labour will point out that nationally they are the only alternative government, so ask you to vote for them. There is little sign of any tacit agreement this time between the two parties to indicate the truth to voters in each constituency. On the ground each local party wants to win and it is virtually impossible to get them to hold back for the greater good.
Then there is conviction. Voting is a civic sacrament for many people, something done with a seriousness not readily abandoned to cynical manoeuverings. After all, voters only rarely get the chance to punish or reward their leaders. If they strongly support a party, say the Tories, they want to put there precious X there on the line to save John Major. It may be a Labour seat, but at least they have had their say. Persuading them to vote Lib Dem instead is unsatisfying. Their loyalty to the party of their allegiance is often stronger than their wish to do down the enemy.
Tactical voting is for those who hate more than they love. But since governments tend to be voted out rather than oppositions voted in, tactical voting ought to appeal to the naturally vengeful instincts of the people.
It is, however, a poor, weak blunt instrument in our present voting system. But the more people can be brought to think tactically, the more it indicates that they understand the grotesque injustice of our first-past-the-post system and the more inclined they will be to support proportional representation in Labour's promised referendum on electoral reform.