I graduated from college in 2008, I have been looking for a job for quite some time now (I do have several part-time gigs carrying me over, so I suppose I should say I'm looking for a more "career-track" type job).
Through the experience I've had with internships, I'm confident that I know what I'd like to do- I want to work in politics, and I'd love to do either policy/research work or communications. While I do occasionally run into the job posting that is exactly what I'm looking for, I also feel like "beggars can't be choosers" to some extent, so I'm still applying for a lot of things that aren't ideal.
My question is, which would be better for me in terms of my future goals: a job with my desired function in the wrong field (ex. a communications position in an industry unrelated or slightly related to politics) or a job in the desired field doing some other function (ex. an administrative position with a political organization)?
My initial thought would be that it would be best to get in with an organization in politics, even if it was doing something like administrative work, but my concern would be that they would just start to see me in that role and that it would be difficult to do something else.
My sense is that you are not thinking about this in the right way.
If you are in a large organization it is far too easy to get pigeon-holed. If you take an administrative position with a political organization you may never get a chance to do anything but administrative work. If you take a communications position in a large company, you might be writing or proofing copy for the rest of your life.
It is far better to seek out an organization that will provide opportunities rather than focus on the field or function. If you get a job as a file clerk in a small think tank you might meet people and be tasked with helping with policy research within 6 months.
Basically, in my experience it is about the organization not the specific job duties.