On May 7, British voters will go to the polls in the most unpredictable general election for decades. Unlike in Japan last December, the British election is anything but a foregone conclusion. Usually confident commentators predict nothing more precise than another hung parliament, with no party winning a majority of seats. In recent opinion polls, the two main parties, Labour and the Conservatives, have both hovered around 35 percent support with only 0.2 percent between them. The only certainty is that Conservative leader David Cameron or his Labour rival Ed Miliband will emerge as prime minister. But which coalition of parties will sit around their Cabinet table, and at what cost, is anybody's guess. Why has British politics become so chaotic? There are four key factors at work.

First, combined support for Labour and the Conservatives has been steadily declining since the 1970s. In the 1950s, the two parties together won more than 90 percent of the vote. By 1979 that figure was down to just over 80 percent. At the last election in 2010 it was a measly 65 percent. With just over a month to go until polling day, neither party looks set to make a breakthrough.

Positive economic news since Christmas has not translated into an upswing for the incumbent Conservatives. Britain's recovery is benefiting the wealthy few, but not the many who have suffered during five years of Conservative austerity. Cameron cannot shake suspicions that he is out of touch with ordinary people, a view confirmed by his inability to hazard a guess at the number of food banks in Britain in a recent interview.