There has been a change in the political weather. So at least it seemed to me on a visit on Monday to West Yorkshire, to watch Andrea Jenkyns try to eject Ed Balls from Morley and Outwood, which the shadow Chancellor holds by only 1,101 votes. This is my fifth election sketch for ConHome, but the first where I came across signs that the words of one of the party leaders are being heard on the doorstep.

A young woman in the village of Gildersome told Jenkyns: “I think Nicola Sturgeon’s holding the Labour Party to ransom and it’s absolutely petrifying.”

And in the neighbouring seat of Pudsey, won in 2010 by Stuart Andrew for the Conservatives by 1,659 votes, an elderly lady promised she would support him, but added: “I’m only voting because I want to keep that Scotch woman out.”

A number of the many undecided voters have been provoked by Sturgeon into backing the Tories. Some of the reasons which already existed for voting Conservative – the improving state of the economy, the hard work of local Tory candidates, the prime ministerial qualities of David Cameron – are underwhelming. These may be necessary conditions for success, but they can also quite easily be taken for granted, or at least seem too undramatic to be used to explain a change of mind.

I have yet to come across voters who are backing the Conservatives out of passionate admiration for Cameron, or indeed Labour out of passionate admiration for Ed Miliband. But it does now seem that Miliband’s weakness (itself a necessary but not sufficient condition for Labour failure) renders him vulnerable to the charge that he would be pushed around by Sturgeon.

Jenkyns said her canvass returns have improved since Sturgeon appeared in the television debates; and Jenkyns also thinks she will beat Balls. When I relay this kind of thing to Paul Goodman, the editor of ConHome, he utters words of caution: “Candidates usually think they’re winning.” But morale among Conservatives in West Yorkshire is higher than I had expected. They find the Conservative vote strong and the Labour vote soft, and are confident that Andrew will hold Pudsey.

Dan Cohen, a Tory councillor in Alwoodley, even predicted that the Conservative candidate, Simon Wilson, could regain Leeds North-East – Sir Keith Joseph’s old seat – from Labour. Fabian Hamilton has held this constituency since 1997, currently with a majority of 4,545.

In Morley and Outwood, Jenkyns has been working for the last two years to unseat Balls. She does not attack him, except when he declines to turn up to hustings, such as those held on Monday night. When she met him at a function, she instead said to him: “Come on, Ed, come and dance.”

Balls replied, somewhat ungallantly: “Andrea, if you and I dance, it’ll end up in the Daily Mail.”

Jenkyns, who is a trained soprano with a website on which her recordings can be heard, suggested they perform a duet for charity, with Balls accompanying her on the piano. Balls excused himself with the plea that he is not a good enough musician.

On the doorstep, it is clearly in some ways an advantage that Jenkyns is a woman. On two occasions, women said “No offence” to me, before explaining a point which they reckoned only a woman would be able to understand.

But a woman who lives in an ex-council house, now owned by its former tenants, did turn to me and say, in the middle of a conversation with Jenkyns about the pros and cons of a referendum on Britain’s membership of the European Union: “Have you met Boris Johnson? Can we have him as Prime Minister? He’s just ace. The world would be a happier place with Boris Johnson as Prime Minister.”

Jenkyns is strongly in favour of an EU referendum, and I saw her talk round a couple of UKIP voters, one of whom – an elderly man living on his own – said: “I’m just thinking UKIP, but now you’re coming and speaking your mind, I’m not sure.” Jenkyns continued speaking her mind, at the end of which he said in a gentle tone: “Well I’ll vote for you, then. It’s very rare I vote.”

Whether he will actually vote in a fortnight’s time, perhaps even he does not know. And the candidate had spent at least ten minutes talking to him, which plainly she cannot do with every voter. But two years ago, she sold her house, gave up her job and devoted herself full-time to campaigning in this constituency between Leeds and Wakefield. She has established strong links with local businesses, has delivered about half a million pieces of mail, and handles about 40 pieces of case work a week. Her mother, Valerie, helps run the Conservative office, established above a hairdresser’s.

Jenkyns would generally introduce herself to voters with some variant of the words: “I’m Andrea, I’m the local Yorkshire lass standing for Parliament.” Mr Balls was born in Norwich and brought up in Nottingham. In some longer conversations, Jenkyns would recount how her father, an ex-lorry driver who set up his own business, died of MRSA in 2011, his weight going down to seven stone: a harrowing experience which made her determined to campaign for the highest standards of hospital care, and to help anyone else who feels let down by the system. She had previously worked in retail management, and as a music teacher.

In the magnificent town hall at Morley, a bust of Queen Victoria faces one of Asquith, who was born in the town and served as Prime Minister from 1908 to 1916. Next to it are the words of that eloquent Liberal about facing “without perturbation, the buffets of circumstance, the caprice of fortune, and all the inscrutable vicissitudes of life”. Such equanimity will be needed by many candidates on the morning of Friday 8th May.

The town is deeply patriotic, and is currently adorned with St George’s flags, in preparation for its annual St George’s Festival, including a procession with St George mounted on a horse. Will Jenkyns be chosen to represent this Yorkshire patriotism? She herself is not a wholly traditional figure: although devoted to dogs, she is a vegetarian, and opposes foxhunting. But she observes with pleasure that judging by the tweets of Balls’s Saturday canvassing expeditions, she can muster more volunteers than he can.

If I were Balls, I would feel immensely irritated by Jenkyns, would try my hardest to ignore her, but would nevertheless be slightly worried by the knowledge that if the Conservatives establish a quite modest national lead, she has good chances of winning.

The suggestion at the start of this article that the political weather has changed could have been prompted by the perfection of the spring day. But voters do display a greater willingness to change their minds, and a burning desire to stop Sturgeon from having any power over their lives.