In the United Kingdom general election May 6, “tactical voting” has become a serious issue as prominent members of the Labour Party push for it as a way to “keep out the Tories.” It’s an issue in upcoming US elections, as well.

Tactical voting is voting for someone besides the candidate you would most want to see win. Normally it is used to stop the candidate you hate the most from winning, by voting for your second or even third choice.

Take, for example, a district where the Conservative candidate polls at 38 percent, Labour is at 30 percent, and the Liberal Democrats are grabbing 20 percent. Imagine you are a LibDem supporter who hates the Conservatives and is simply unhappy with Labour; after concluding that your Liberal Democrat candidate will not win, you decide to vote for the Labour candidate because he or she has the best chance of beating the Tory. That’s tactical voting.

It has a serious effect. Because of the election laws, makeup of districts and spread of support across the country, one party could get a total number of seats in Parliament completely disproportional to the popular vote. The party with the least votes could even win the most seats.

Tactical voting is bad for democracy, but it can be eliminated

Tactical voting should not be part of a democracy. Fortunately this is a solvable problem that only emerges because the UK (like the United States) uses an election system of single-member districts where the winner is whatever candidate in the crowded field gains the most votes, called a “first past the post” system. Other countries use different systems like proportional representation, which allows the legislature to represent the diverse will of the people. A system of party-line proportional representation provides each party with a number of seats relative to its overall popular vote. That reduces the tactical value of voting for a party that is not your top choice.

Another way to deal with tactical voting is with an instant runoff system or even a top-two runoff system. An instant runoff system allows people to vote for their preferred candidate, but state who their second or third choice would be if their candidate fails to get enough votes. While it does not eliminate the possibility that you might be “technically” voting for your second choice, it allows every person to vote for who they think is the best candidate without fear they are indirectly helping to elect the candidates they hate the most.

Tactical voting in the USA

Tactical voting may occur in the HI-01 special election. With two Democrats in the race, the Republican might win with a small plurality. The situation might lead some voters to pick their less favorite of the two Democrats if they think that individual has the best chance of beating the Republican. We will probably see the issue play out in the three-way Senate race in Florida, too. People who prefer newly minted independent Charlie Crist may end up voting for Democrat Kendrick Meek (or vice versa) based on who may have the best chance of stopping Republican Marco Rubio.

Of course, in America, we are not just seeing tactical voting in a few rare races but all the time. We have a British-style system of single-member districts with “first past the post” voting, which drives us intractably toward a two-party system, despite the desire by a large part of the country to have a more diverse set of legitimate choices.

In the United States, we don’t really have strong third parties or many independent candidates because our system produces the fear of the “spoiler effect.” We fear a third party can’t win so we don’t want to waste our vote on it. As a result, those parties can’t get enough support prove to people they can win, which is the only way to make most voters comfortable with them. It is a serious chicken-and-egg problem, but the spoiler effect is an artificial problem created by our electoral system and it could be solved.

In the UK, the Liberal Democrats, who have had to battle against a two-party system for years, might use the power they gain from this election to deal with some of the weaknesses of their election laws and create a system that better represents the will of the people. The issue for us in this country is that those with the power to solve the problem here are all Democrats and Republicans, who most benefit from leaving the current setup unchanged.