Nick Clegg has said he accepts the public did not share his desire to reform the voting system and is ready to "move on", as the electorate delivered a decisive rejection of a change to the way MPs are elected.
More than twice as many of the 42% of voters who turned out for the UK-wide referendum said they would rather keep the present first-past-the-vote system than switch to the Alternative Vote (AV).
With only Northern Ireland left to declare, the No to AV campaign had attracted 12.6 million votes to the Yes camp's 5.9 million - 68% to 32% - and just 10 of 439 local areas had endorsed a change.
Mr Clegg - whose party passionately supports voting reform and who secured the national vote as the main prize in negotiations to form a coalition government with the Tories last year - said it came as "a bitter blow".
"I am a passionate supporter of political reform, but when the answer is as clear as this, you have got to accept it. In a democracy when you ask a question and you get an overwhelming answer, you just have to accept it and move on," he said. "This is a bitter blow for all those people - like me - who believe in the need for political reform."
Defeat for his cherished policy came on top of a hammering for the Lib Dems in councils across England, as well as elections to the Scottish Parliament and Welsh Assembly in a bruising day at the polls.
The Deputy Prime Minister insisted though that the result would not prevent the power-sharing administration continuing - despite an often vitriolic campaign which saw the Westminster partners exchange sharp public blows.
"The wider job of the Government and the Liberal Democrats in Government will continue - to repair the economy, to restore a sense of prosperity and jobs and optimism to the country. That's the job that we have started and we will see it through."
Prime Minister David Cameron welcomed the "clear and resounding" result but said there would be no celebrations as he attempted to reinforce the message that the coalition would see out its five-year term through to 2015.
Labour leader Ed Miliband, who failed to secure the support of a majority of his own MPs for a Yes vote, said he was "disappointed" by the result but added: "I think the people have spoken very clearly on this issue and it is a verdict that I accept."