Unlike some who vote for a particular party regardless (VQ's comment re voting for a chimpanzee if it was wearing a red rosette for example) I tend to start with a local perspective, which I apply to general elections, local council elections and more recently the one relating to the police commissioners.
I read every piece of literature and go to the hustings when possible. I then make my choice as to who to vote for. My choice of candidate doesn't always win, but at least I can feel confident that I have made a reasonably informed decision.
Therefore I would not be able to say that I was a Tory voter, a Labour voter or even a Monster Raving Loony Party voter, although the cnadidate for the latter did actually get elected in one of the local council elections somewhere in the county (Devon).
There are certain issues that if looked at on a national basis, seem reasonable, but when considered locally are not.
For example the move for increased house building. Locally we have more houses than are needed, but a dearth of jobs. My husband has to live away during the week as he couldn't find anything locally, and I have been out of work since being made redundant in March of last year.
Wind farms too are very relevant round here.
So basically I put the needs of the immediate area first in my mind, and look for a politician who understands them and can make sensible, achievable proposals to deal with them