London (AFP) - Britain votes in a general election on Thursday in which Prime Minister David Cameron could lose power and no one party looks set to win a clear majority.
Here are the issues at the heart of the campaign:
- Economy -
Britain has a budget deficit of some Â£90 billion (124 billion euros, $130 billion). While the main parties all want to eliminate it, they disagree on the depth of the cuts needed to do so.
Cameron's Conservatives originally vowed to eliminate the deficit by 2015 but now say they have halved it. They are pledging at this election to finish the job by 2018-19.
Ed Miliband's main opposition Labour party has been more flexible on timing, saying they would eliminate the deficit by the end of the next parliament in 2020.
The respected Institute of Fiscal Studies research body says there are "big differences" between the two, with Labour set to increase taxes on the rich significantly and the Conservatives set to cut state benefits.
Meanwhile, the pro-independence Scottish National Party (SNP), which could play a key role in propping up Labour after the election, wants to end austerity policies altogether.
- EU -
This could be the election which decides whether Britain stays in the European Union or not.
Cameron's Conservatives have promised a referendum on whether to leave the EU by 2017 if they win outright. The Liberal Democrats support a referendum if there is major treaty change but would campaign to stay in.
Labour opposes a referendum as does the SNP, which also wants Scotland to have a veto over any British departure from Europe.
Nigel Farage's UKIP, which looks set to win only a few seats, wants Britain to leave the EU straight away.
- Immigration -
A highly emotive topic for many voters.
Net migration to Britain, which has a population of 64 million, stood at nearly 300,000 last year.
Many people come to Britain from eastern EU countries such as Poland, increasing demand for public services and competition for jobs.
The Conservatives have not delivered on a previous pledge to cut net migration to below 100,000 a year. They now say they want to get the figure into the tens of thousands and reform welfare rules for EU migrants.
Labour also wants to reduce migration, pledging to hire more border staff and tighten rules on state benefits for migrants.
UKIP takes an even firmer line, urging a five-year ban on immigration by unskilled workers.
- Health -
The state of Britain's cherished National Health Service (NHS), which provides free care at the point of delivery, is another hot topic.
Labour accuses the Conservatives of overseeing a privatisation of the state-run service through a programme of free market reforms.
It wants to reverse these and hire thousands more doctors and nurses with the proceeds of a "mansion tax" on big houses.
The Conservatives, who say their policies are making the service more efficient, have pledged to increase NHS spending by Â£8 billion a year by 2020.
Doctors and nurses have even taken to the campaign trail themselves in the newly-formed National Health Action Party (NHAP) to campaign against cuts.
"The main parties are promising a little more funding but not enough to meet needs," Louise Irvine, a doctor, told AFP in the South West Surrey constituency where she is standing as a candidate.