The referendum for Alternative Voting (AV) to replace the existing “first past the post” system looks likely to be defeated on May 5, polls reveal.

A  ComRes poll for the Independent shows a stonking 66% of voters have made up their minds to vote No to AV compared with 34% for the yes campaign. Since last week the No campaign have increased their lead from 60% to 66%. 15% of voters are yet to make up their minds.

The proposed AV system – in which voters would rank candidates in order of preference – is the Liberal Democrats’ baby and if defeated would be a huge blow to Lib Dem leader and deputy Prime Minister Nick Clegg who convinced the conservatives to hold the referendum as a condition of forming a coalition.

If the AV referendum is defeated it could put untold strain on the Lib Dem/Conservative coalition led by Prime Minister David Cameron.

“Pollsters tell me that the gap in the No campaign’s favour has been widening gradually as the campaign has gone on,” said Sky’s chief political correspondent Jon Craig.

“If the result is anything like that – 66% to 34% – that is horrendous news for Nick Clegg and the Liberal Democrats.”

“It is also bad news for Ed Miliband, the Labour leader who has been supporting AV.”

Speaking of whom, Ed Miliband has made a last ditch appeal to get people to vote Yes to AV.

The opposition leader urged voters not to use the AV referendum to “kick Nick Clegg” and said the referendum presented a “once-in-a-generation opportunity” to change Britain’s political system for the better.”

AV voting system explained