Simon Carr: Nancy Mogg? No, it's Annunziata Rees-Mogg, actually

The two candidates fighting for possession of this glorious Somerset constituency – this green-laned, river-milled, Sunday evening serial of a place – are each the embodiment of the party to which they belong.

David Heath, the "Lib-Deb" (as he was called in the cattle market) is hairy, humorous, decent, intelligent. He is a Liberal. He is a party man without being unpleasantly partisan. He is local, he believes in Parliament.

The Conservative candidate has a five-syllable Christian name, was a financial journalist, and is a fragrant child of the county bred between old stone walls.

How the constituency of Somerton and Frome turns out may tell us how the country turns out. Who do we like more?

First, to the cattle market to see David Heath. He was one of the shadow Leaders of the House and is always worth the price of admission.

Heath has compromised with the electorate to the extent of trimming his beard. "It's an election! I trim it every five years" – yes, whether it needs it or not, arf, arf.

So, as we're here, let's get professional. What are the figures, what are the polls saying, what's the swing and has it swung, how hard is the soft vote and how soft is the hard and... They do all insist canvassing and campaigning works. I'm not at all sure they're wrong. I understand it's all to do with getting the vote out.

But everything's tight, it's all very close. "I've won this seat three times without anything as vulgar as a four-figure majority," Heath says. It was 130, then 539, and last time 812. It's so thin that the "personal vote" – that fabled quantity – might swing it.

They like Heath; it's clear by the way they don't pelt him with fruit or animal waste (both are readily available). He once hit a boundary off the bowling of Colin Dredge, "the demon of Frome".

One question he'd like to ask Gordon Brown: "What party will you support in the event of a hung parliament, if Labour is the smallest party?" It is possible now to dream the impossible dream.

The Tory candidate has a name that is visible from space. She famously refused to shorten it to Nancy Mogg. She herself is petite, 31, unmarried, and the daughter of one of Somerset's prominent non-voters. Lord Rees-Mogg – a member of the commentariat so unfailingly wrong he influences bookies' odds when he pronounces – is her father.

Annunziata (she was born on Lady's Day) says her family life is more diverse than you might assume and points out that one sister had campaigned for the Greens before switching to the Liberal Democrats (she has delivered leaflets for David Heath, under her married name). She has Blue Lagoon eyes, a serious manner, and one of those unplaceable accents that mark out a specific quintile of the upper-lower-upper class. Her quiet way of expressing Conservative views makes people listen. Liberty, Euroscepticism, sound money – but not so sound as to rock the recovery. Her conversion rate, her team says, is high. How many converts has she? Who knows. There is nothing so vulgar as an Excel sheet of supporters. So how will she get the vote out, I wonder. "I don't think the electorate want to be bullied like that."

Such manners. And Tories like that. Two very different approaches. But then whoever wins, it'll probably be Nick Clegg's fault.

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