M0nica
growstuff the rural part of the constituency cannt account for all the Conservative vote because the population of the rural area is just too low to do so, particularly as not everyone there will vote for the Conservatives.
Most of the Conservative vote comes from the rapidly growing towns; Wantage and Grove, Didcot, Faringdon. Areas where 10,000 and many more new houses have been built in the last ten years and it isn't the old settled population buying them, it is the younger family forming groups moving to work in the area, whether immediately in the constituency, or in Oxford or Newbury.
I have found this site very useful. www.electoralcalculus.co.uk/fcgi-bin/seatdetails.py?seat=Wantage
MOnica I don't know your area at all, but I do know mine. I've lived here for 35 years and have been active in local politics for much of that time. I have been out with candidates knocking on doors and have stood around windy marketplaces talking to people. The LibDems have built up a wealth of local knowledge about how streets and hamlets vote. Obviously it's not an exact science and there will always be exceptions, but we have a fair idea how people vote and why down to individual streets. We know how new building will affect voting patterns and target resources on canvassing, if we think they will be potential voters. We don't usually bother with areas where we know there will be almost no support because we don't have the resources to cover everybody. Of course, some of those people then complain that nobody has leafleted them. In truth, all some of them want is an opportunity to rant.
I don't know who is moving to your area. Here it is often people moving out of London, who tend to be wealthy (from selling property) but socially liberal. They are usually graduates, who tend to be far less conservative (with a small "c") than lifelong country dwellers. I would be surprised if the pattern in your area is very different, but it could be. That's why it's very important for political parties to have strong local networks of people who really understand the area first hand, not just from third party statistics.