Pencilvester

@GreenEyedTrombonist (Nice I got it) I just looked more closely at the CVs of the professors I identified as possible research matches and realized that I couldn't make as good a case for fit as I initially thought. My criterion has been to apply to programs where two or more faculty members study similar enough stuff and at both programs there was less than 1 who did (as in, even the one person in each department who studied similar stuff would've been a bit of a stretch).
How have you been going about your search?/How did you pare down your list?

@Pencilvester I was brand new to the field when I applied last year so I don't know about rankings. Like @gradswag has stated, it really is specific to the subfield. The NCA rankings are quite old but still a useful place to start. The NCA also has a list of "hot" new publications, looking at where those authors teach may help. 
In terms of "slots" by subfield, there are some schools that do something like that (UW Madison, for example) but not all do. I know what it's like applying from another field and worrying about whether I was aiming waaaaay too high or not high enough etc. But I'd still say it's best to really look at which schools best fit your research interests and talking with potential advisors/ DGS. Communications is a pretty Midwest heavy discipline so you may miss out on really good programs if you focus only on schools that are generally "good schools."

It depends on a few factors and it varies from year to year, which is why I would recommend reaching out to faculty of interest to see if they would be taking new students. I know that Rutgers will fund one student per subfield per year in their comm department. That is not super common, and their department is a special case. Most often schools look for research fit, so do you do what people in the department do. So to answer your question, no they will not necessarily fill slots dedicated to certain specialties. Faculty tend to stick to their research area, so it is competitive in a subfield when only a few (prolific) people are researching in that area in a department and most applicants apply to work with those few professors. In any given year, they might be looking for a certain type of student who fills a need for them (last year they admitted x # of students in interpersonal, so this year they want to admit a few more health comm students, for example). The only way to really know if they are admitting students in that specialty is to reach out and talk to a faculty member/DGS in a department to see. The competition comes into play when you want to work with a person that every other applicant wants to work with, and that is usually subfield specific.
 

I am really unfamiliar with the area of political comm in general, so I don't want to give you bad information about the rankings for that specialty. In looking at your list more generally, you would be applying to many of the powerhouse programs in the field (UPenn, UW-Madision, Ohio State, Penn State) that are more competitive across specialties. I think that U-Penn and Cornell get a lot of applications because they are ivy league, and Michigan because it might as well be (though I am less familiar with their comm program). The other schools I don't know too much about, so I don't want to speculate on their competitiveness or ranking. 
So, with my disclaimer that I don't know all that much about political comm/deliberative democracy, I think your list is generally leaning towards the competitive end of the spectrum. I would say that you should reach out to faculty members you would like to work with/whose work you are familiar with, or the director of graduate studies in their department and ask them about their program. I am not sure how much you have delved into the comm field, but our flagship organization is NCA, and they have a doctoral program guide that you can find here. They breakdown programs by specialty, which might help you develop a more comprehensive, well-rounded list.
Hopefully someone can hop on here and give you more directed advice to poli comm.

I am not sure if I can give you help without a little more information about your interests (communication is a very broad field, and these programs have vastly different strengths). What are you planning on studying (health, media, interpersonal, rhetoric, journalism etc)? Do you think you are a more qualitative/quantitative scholar? Do you have research experience? Additionally, some of these schools have two comm departments. Like Penn State, for example. We have the school of communication which is primarily media studies, and comm arts and sciences which houses rhetoric, health comm, interpersonal, and social influence folks. These schools rank differently/are more competitive depending on what you are planning on studying.