UKIP leader Nigel Farage has told a press conference that "never again" will people say voting for the party is a wasted vote, following the Eastleigh by-election where the party finished second.
He added that he intended to capitalise on the "tremor" UKIP had created in Eastleigh and turn it into a "national political earthquake" at the European elections next year.
The Labour backbencher Austin Mitchell has described Labour finishing fourth in the Eastleigh by-election "a disaster":
Eastleigh disaster. Labour needs a nationalist appeal. The nation is being betrayed,weakened and sold down river.We sd say so
The Conservative MP Conor Burns appears to blame local councillors rather than the central party leadership for the party's poor performance in the Eastleigh by-election:
The Eastleigh result is in no small part a consequence of withered local organisation caused by an absence of Council leadership or vision
The wider political impact of parliamentary by-elections often turns out to be more important than the result – Eastleigh is no exception.Read the full story ›
Speaking after the Eastleigh by election result in which they came third, Prime Minister David Cameron has said the result was "disappointing".
He added that the Conservatives would win back voters by "remaining true to our principles".
The Labour party candidate John O'Farrell has tweeted on the morning after his defeat in the Eastleigh by election.
Mrs O'F just woke me with an affectionate 'Mornin' Loser!'
Had hoped more would switch from Lib to Lab. Some did, but as many of ours went to UKIP. Lab % share up slightly. Result feels OK in context
Nick Clegg told Liberal Democrat supporters they had won a "stunning victory" in Eastleigh, despite the "exceptional circumstances".
Prime Minister David Cameron said today that the Eastleigh by-election result was "disappointing" but he was "confident" that the Conservatives could win back support at the general election.
Liberal Democrat leader Nick Clegg has thanked party supporters after the party held the seat of Eastleigh in yesterday's by-election.
He said: "This has been a by-election we have had to fight in exceptional circumstances. Our opponents have thrown everything at us. We held our nerve, we stood our ground, we worked as a team, we went out and campaigned on every doorstep. We overcame the odds and won a stunning victory."
The UK Independence Party's Diane James, has described beating the Tories to take second place in the Eastleigh by-election was a "humongous" shock that represented a "seismic shift" in UK politics.
Conservative candidate Maria Hutchings polled 10,559 votes - more than 1,000 behind Ukip, which snatched huge chunks of the coalition parties' 2010 general election vote share, taking more than 27% of the total.