Election too close to call

The latest buzz word in the clubby world of British politics is "hung Parliament".

It means an election so close that no party receives more than half the seats in the House of Commons, the lower house of Parliament.

It is commonplace in most parliamentary democracies, but hasn't happened in Britain for more than three decades - and the very idea has sent the financially battered country into a tizzy, causing the pound to tumble.

Prime Minister Gordon Brown must call a vote by June 3, with an early May date deemed likely. The widespread assumption that Conservative Party leader David Cameron would win an outright majority in the new Parliament has evaporated.

"It's just about 50-50 that we'll have a hung Parliament," said Bob Worcester, founder of the Ipsos MORI polling firm, which will conduct Election Day exit polls for British news stations.

Voters seem tired of Brown and the Labour Party apparatus after 13 years in power, but it is not clear if they have really warmed up to Cameron in sufficient numbers to give him full control of Parliament.

No one knows exactly how a hung Parliament would play out. An election in which no party gets an absolute majority raises a number of possibilities:

There may be political horsetrading leading to a coalition government, a rarity in Britain; a weak minority government chronically unable to muster policy support; or a second election, as was the case in 1974, another year in which Britain was going through an economic crisis.

The uncertainty has rattled the financial markets. Traders would prefer to see stability and predictability in a country coping with frightening levels of debt.

The post-election period would also raise the profile of Queen Elizabeth II, who is head of state but in reality prohibited from having a direct political role. As monarch she would have to grant one of the party leaders permission to form a new government, and she would also have to okay a second election if needed.