Voters are heading to the polls today in a UK-wide referendum to decide whether or not to change the Westminster voting system from first past the post to the Alternative Vote (AV).

Under AV voters would rank candidates in order of preference. If no-one gets 50% of votes in the first round of voting, the candidate with the fewest votes is eliminated and their backers’ second choices allocated to those remaining ensuring that the eventual winner has at least 50% of the vote.

Changing the electoral system from first past the post to AV could transform the political landscape in the UK with many Tories saying Prime Minister Cameron should never have accepted a referendum as a condition of the coalition with the Lib Dems as they believe AV could hamper their performance in future elections.

However a recent ComRes Poll shows that AV will almost certainly be defeated at the polls today (May 5) with 65 % voters saying they will definitely be voting no.

If the ‘No’ campaign wins, Deputy Prime Minister Clegg will face increasing pressure from his party who already believe the party have sold out over tuition fees.

Meanwhile Ed Miliband has taken a swing at the previous Labour government saying they “should have” tried to change the UK voting system while they were in power. He claims the party didn’t pursue a referendum because it had “too big a majority,” but that he argued for it at the time.

Mr Miliband is campaigning for a Yes vote.

AV looks set for heavy defeat at polls

AV explained