Labour's video ridicules Conservatives John Redwood and Nick Bourne, and Plaid Cymru leader Ieuan Wyn Jones
Leading Welsh Labour figures have produced an online video portraying the Welsh Tory leader as a vampire and the Plaid Cymru leader in a clown hat.
Ahead of the European elections, former Welsh Secretary Peter Hain is among those promoting the video , which has been attacked as "childish".
It features the tune of Tom Jones' Delilah to lyrics by MEP Eluned Morgan.
"Why, why why" also claims Labour's assembly coalition partner Plaid was against European aid money for Wales.
The song, on a new website Aneurin Glyndwr, also attacks the Conservatives' economic record under Margaret Thatcher.
We are amazed this childish video and website has been endorsed by such high-ranking Labour figures
Welsh Conservatives on Labour's video
Describing Plaid as "very shoddy", it says voters should choose Labour rather than Plaid to avoid a breakup of the United Kingdom and increasing poverty in Wales.
The decision to portray Welsh Conservative leader Nick Bourne as a vampire, complete with fangs and a cape, will raise eyebrows, as Labour complained bitterly about a dossier released by the Tories last year which called Rhodri Morgan the "clown prince of Wales".
Mr Bourne later withdrew his support for the document and made a personal apology to Mr Morgan.
The video, which puts a clown hat on Plaid leader Ieuan Wyn Jones and some of his party colleagues, ends with a plea to voters to choose Labour at next June's European elections, and a picture of the party's four Welsh candidates.
A Welsh Conservative spokesman said: "We are amazed this childish video and website has been endorsed by such high-ranking Labour figures.
"People faced with losing their job or their home want to know how political parties can help them survive the recession.
"After a decade in government Labour clearly lacks the confidence to defend their own record or put forward any vision for the future."
A Plaid Cymru spokesman said: "This is probably THE worst website ever produced by members of a mainstream political party. It is without doubt Labour's John Redwood moment.
"They have seriously lost the plot. Wales is in the middle of an economic crisis and their politicians are singing Delilah on Peter Hain's home-made Karaoke machine. Serious times call for serious politicians.
"If this is the best the infamous New Labour spin machine can now manage then they are in a worse situation than anyone had imagined."
Our aim is to build a network of progressive people who are interested in politics, but are not obsessed with it
Peter Hain MP
The senior Labour figures say that the new website is "an Obama moment for Welsh Labour".
Its logo depicts the Labour minister Aneurin Bevan, credited with establishing the national health service, alongside Owain Glyndwr, often portrayed as a hero who opposed the English crown and established a Welsh Parliament in the 1400s.
Leading Welsh Labour activists and politicians have been studying President Obama's new media strategy and have met with his top web campaign advisers.
The new initiative is being led by Peter Hain, who has pushed for an overhaul in Welsh Labour's campaigning efforts, particularly online.
'Opportunism and errors'
It marks Labour's response to other parties' online efforts. Earlier this month, Plaid Cymru launched their WalesCan site, designed to put the arguments for Welsh independence in the next two decades.
Plaid Cymru's leader and colleagues are among those mocked in the video
Labour says that the Aneurin Glyndwr site is designed to "expose hypocrisy, opportunism and errors by the Tories, Plaid and Lib Dem politicians".
Mr Hain said: "Our aim is to build a network of progressive people who are interested in politics, but are not obsessed with it.
"That is the one danger of blogging, it can become the preserve of a self-appointed elite. We already have the core activists, what we need to do now is reach out and mobilise the millions of people who, although they might never go to a Labour Party meeting, will work hard to stop the Tories getting into power again."
MEP Eluned Morgan added: "The Welsh Tories have mega-money - much of it raised from the same City bankers who gave us the credit crunch.
"But we in Welsh Labour have passion and energy and with initiatives like Aneurin Glyndwr we will take on and expose the hollow rhetoric and opportunism of the Tories, nationalists and Liberal Democrats in Wales."
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