Britain's opposition Labour Party leader Ed Miliband speaks at the presentation of their business manifesto in central London March 30, 2015.[Photo/Agencies]

The future of the British National Health Service (NHS) will be a major battleground, with all parties vowing to protect what is regarded as a cherished institution, free health care at the point of need. The Conservatives have been accused of paving the way for more of the NHS to be privatized, with claims that major U.S. health providers are already circling over Britain like vultures ready to swoop.

In Britain's House of Commons there are 650 MPs, representing constituencies in England, Wales, Scotland and Northern Ireland. A party needs to win at least 326 seats to have an overall majority.

In 2010, for the first time since 1974, no party crossed the 326-seat threshold, creating a hung parliament. The Conservatives won most seats, but their tally of 306 - 96 more than they won in 2005 - fell 20 seats short. Labor ended up with 258 seats - 91 fewer than the 349 which gave them an overall majority in 2005. The political horse trading led to the Conservatives forming a coalition government with the Liberal Democrats who won 57 seats.

Liberal Democrat leader Nick Clegg, who became Deputy Prime Minister in 2010, broke a pledge to oppose raised student tuition fees, sparking student protests and leading to his party being virtually wiped out in many local councils.

The election on May 7 will give the British public the chance to show Clegg whether or not he has been forgiven. If the pollsters are correct, it seems the public is still not in a forgiving mood.

Looking forward, it seems the upcoming election will be the most unpredictable and fascinating one in Britain in living memory.