Debbie McGee reacts to Strictly Come Dancing support from Theresa May

"I mean it's totally unreal, isn't it?" Debbie tells RadioTimes.com.

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"That's the thing about this programme. You can't believe that all these people are talking about you, and to have the Prime Minister saying that she's rooting for you is just incredible."

Can anything top that? "The Queen, I suppose."

The former magician's assistant, 58, admits that she has "absolutely and completely" exceeded her own expectations about how she would perform as the oldest woman in the competition.

But now she has reached the quarter-final, all those doubts are gone. It's game on for the final.

"I just see myself with that Glitterball," she declares.

"I was given this advice last week, actually, by Suzanne Shaw, who said when she won Dancing on Ice, she just kept imagining herself with the trophy. So I'm just imagining myself with that Glitterball."

This week, Debbie and her partner Giovanni Pernice are taking on the American Smooth to the song Memory from the musical Cats – and it's a routine with a lot of emotional resonance for Debbie.

"I think that it suits everything that's happening in my life at the moment, so it's something that I'll be able to portray," she says. "The song is Memory from Cats, so it's beautiful, and it's all the things that I go through every day, memories of working with Paul, and that life is changing.

"The end line is, 'A new day has begun,' and that's what it feels like being on Strictly."

On her late husband, the magician Paul Daniels, she adds: "He's always with me."

Debbie and Giovanni were the first (and, so far, only) couple to earn a perfect score on Strictly 2017. Their week one performance was so impressive that all the bookies immediately reassessed their odds of a Debbie McGee victory.

"It's great to be my age and to get through to the quarter-finals, and for everyone to say that I'm being inspiring to older women and whatever, is fantastic," the 58-year-old says.

Does she feel like she's doing it for the older ladies? "Yes, I do. Because I get so many messages every single day, and actually it does fire me on as well. Because I think, they would all like to be in my shoes and they're living it with me. And that's very important."

She adds: "I certainly wouldn't have done it without Giovanni; he knows how to push me and pull my performance quality out."

Debbie and her Italian pro partner Giovanni, 27, have been one of the power couples of this year's Strictly.

"He's been there on the days I've been sad with a hug, or if he thinks, 'right I need to push her,' he knows when he can push me," she says.

"And I totally respect his work ethic and his knowledge - not just of dance, but of performing, of the cameras, of the whole Strictly set-up - he's really learnt his job. And I just love that in people, so that totally inspires me and makes me want to work harder."

Strictly Come Dancing airs on Saturday 2nd December at 7.05pm on BBC1