OXFORDSHIRE’S tightest Parliamentary seat may have just got even tighter.

Changes proposed in the re-drawing of England’s constituency map could have meant Liberal Democrat Evan Harris holding on to Oxford West and Abingdon with the second smallest majority in the country at the last General Election.

The Oxford Mail has calculated Dr Harris would have won by 25 votes under the proposed changes.

Instead, Conservative Nicola Blackwood secured a 176 majority after an election night recount.

There is no ward-by-ward break down at General Elections, so our figures are based on voters’ party choices during local elections.

The Boundary Commission for England yesterday published its proposals to even out the number of voters in each constituency and reduce the number of English seats from 533 to 502.

Its report suggested moving four Oxfordshire wards to new constituencies and renames both Oxford seats.

Henley constituency would stretch even further north, with the villages of Ambrosden, Chesterton and Launton, near Bicester, joining the vast rural Conservative stronghold.

And Radley, on the outskirts of Abingdon, would become the sole Vale of White Horse ward in the Henley constituency.

Carfax ward in Oxford city centre, which moved into the Oxford East constituency ahead of the last election, would be handed back to the newly renamed Abingdon and Oxford North seat.

Oxford East would be renamed simply Oxford.

The boundaries of David Cameron’s Witney and Ed Vaizey’s Wantage constituencies are set to remain unchanged.

Both Radley, which is leaving the Oxford West and Abingdon constituency, and Carfax, added to it, have a history of voting Lib Dem.

But past voting data suggests the larger Carfax ward, which includes a sizeable student population, would have brought enough votes to push Dr Harris over the winning line in 2010.

Miss Blackwood said: “Boundary changes are not about my electoral chances, in 2010 or 2015.

“It is about ensuring that these proposals are right for the constituency, and that the people of Oxford West and Abingdon are properly represented and properly linked with their communities.

“My major concern is that the removal of Radley will make it an orphan ward and cut it off from its very close ties to Kennington and Abingdon.”

And Dr Harris added: “I do not think it is appropriate for Henley constituency’s boundary to cross the Thames at Radley.

“That is fundamentally wrong, and the Thames and the Cherwell ought to be respected as natural boundaries.”

But Dr Harris hung up when asked whether he hoped to fight the seat again at the next General Election.

Henley MP John Howell, who is set to see Radley become part of his constituency, said: “The proposals are quite geographically well drawn and smooth out some of the stranger boundaries, “They have a geographical coherence to them, and they also ensure that the constituency keeps the character of many small villages.

“I already deal with two district council areas, and adding a third will not be a problem at all.”

But in the north of the county, villagers in Ambrosdon, Chesterton, Wendlebury and Middleton Stoney fought previous attempts to shift them into the Henley constituency in 2003.

Former Chesterton Parish Council chairman David Chapman said: “We are associated and near-joined with Bicester now, and there does not seem any sense behind it.

“Henley is a long way away.”

Banbury MP Tony Baldry said it was “sad” to lose the villages, but with 90,000 voters his constituency had become one of the largest in the country. He said: “It is simply a reflection of the fact Banbury and Bicester are two very fast-growing towns.”

The public have 12 weeks to have their say on the proposals at consultation.boundary commissionforengland.independent.gov.uk.

In Oxfordshire, only the newly renamed Abingdon and Oxford North result could hinge on the boundary changes. They could see the seat pick up another 3,875 voters in Carfax, but lose 1,982 in Radley.

Already the county’s most marginal seat, it is impossible to say with certainty what would have happened under the proposed boundaries in 2010, because General Election results are not given for individual wards.

But we can use recent local authority polling results to predict how Carfax and Radley residents might have voted in the national poll.

Assuming the same 65.3 per cent turnout for the rest of the constituency, Nicola Blackwood, above right, would have lost 462 votes from Radley, and picked up 517 from Carfax.

Evan Harris would have lost 695 from Radley, but picked up 951 in Carfax, handing him a wafer-thin majority of just 25 votes.