She plays the character of Helen, a harassed mother trying to cope with poor schools, NHS waiting lists and rising crime and increasingly fed up with the policies of the Tories.
She tells her complacent husband Paul, who is reading a Daily Mail-style newspaper with the headline `Major: I Want Five More Years': "They don't deserve five more weeks, those people." Later, as she blows out a candle at a children's party, she fervently wishes that John Major will lose the election. "Next time the Tories would stop at nothing. Enough is enough," says a voiceover.
Bunton, 36, is now tipped to be the star of election year in the wake of the celebrity attained by Scott Woods, the left-wing actor whose eyes were superimposed on to Tony Blair last year for the Tory "Devil eyes" advertisement. She also follows in the footsteps of the family who became embroiled in the "War of Jennifer's Ear" after their daughter's 11-month wait for an ear operation was featured in a Labour Party broadcast in 1992. The six-year-old girl's parents later turned out to have differing political views and subsequently split up.
Despite such controversies Labour apparently took few precautions over the actress's political bias, but have struck lucky in their choice of a firm Labour voter for the party's own version of the "Oxo mum".
"They don't ask if you are a Labour voter when you audition [for party political broadcasts]," Bunton revealed yesterday. "But they do ask if you have been a paid-up member of a political party, which I wasn't."
The actress who played Dr Jessica Hardman in Medics and stars in the BBC2 comedy Grown Ups as Mel, a disillusioned social worker, said she had once voted Tory because she didn't know any better.
"I was 18 and I was confronted with the slip and Margaret Thatcher's name was on this piece of paper and I thought, `Let's have a woman prime minister.' I was very naive. I found myself with the vote and I didn't know a damn thing about the political parties. They should teach political education in school."
The public-school educated actress, who lives in south-west London, was brought up in Cambridge and read English at Oxford. She is single and shares many of Labour's concerns."One listens to the radio and gets terrified, hearing about the terrible divide between schools and the people who can afford to give their children a good education and the people who can't," she said.
"I can't talk about politics but I do have a visceral belief in the Labour Party from a humanitarian standpoint. They are more for an equal world than anyone else, and more concerned about the elderly."
She added that she found the situation with the health service "just so depressing". "I can't help having a sneaking feeling the Tories do want to dismantle it. The divide between the haves and have-nots is getting bigger and bigger."Reuse content