For some PhD programs, this may be a problem. Many PhD programs have a minimum GPA requirement of 3.3 or higher.
Which programs are you looking at?
This requirement isn’t really set in stone, but, to bypass it, you would require a potential advisor to specifically request you, or you would need some glowing LoRs from top people in your field.
Here is the thing - unless somebody is independently wealthy, they cannot do a PhD unless they have 5 years of financial support (tuition + stipend) for the PhD program. This is expensive for the program, so they tend to be picky about who they select.
That means that you have to demonstrate that you are a good bet for them. You have to show that you can do the coursework, and, more importantly, that you will be able to perform a large body of research at a very high level.
Regarding your first question - admissions to PhD programs do not involve admission officers. PhD student applications are reviewed by the graduate committee of the program. The committee includes faculty and grad students.
They look over your application. Your application does not include essays.
It includes:
A. A cover letter, which is a good place to demonstrate that you understand what a PhD program in Poli Sci entails.
B. Your CV. Make sure that it is an academic CV, and that it does a good job of being professional and presents your experience in the best light possible.
C. Letters of Recommendation, which are critical. They should be, as I wrote, from people who can attest to your research and academic abilities.
These are the three most important parts of your application.
D. You will add your transcript, so they see that you have the coursework needed, and that you did well on the courses which are important in your field.
E. GRE scores. Not all programs as for GRE scores, and more programs are dropping them as a requirement, but many still do. You will want your scores to be at least in the top 80th percentile, and it would be better to have them higher.
F. You may be requested to add some examples of your work - papers, presentations, etc, from your classes, or perhaps conference presentations or peer reviewed articles. Even if these are not specifically requested, you may want to see if you have the possibility of submitting supporting material.
An important thing to remember is that almost all requirements can be waived if a faculty member in a PhD programs wants you to be their student, or if you have a very good LoR from a top person in the field. A friend of mine was accepted to a good PhD program with a 2.7 GPA, because she had been a field assistant for one of the top people in the field for few years, and he was able to attest that her research skills for this particular discipline where absolutely top notch. I know of another students whose GA was only so-so, but it was in entomology and he was known in the discipline as a top amature entomologist (he got a B in my class, but I wrote him one of the most enthusiastic LoRs I have ever written). He has finished his PhD and is doing a post doc.
What you should be doing is:
A. learning all that you can about Poli Sci research, and about the particular topics that interest you
B. Reaching out to potential PhD advisors in graduate programs which interest you.
While having a good GRE score can help you, these two activities are critical. Without them, it will be very challenging for you to be accepted to a PhD program.
As for your question: it is unlikely that you will suffer discrimination based on racial or ethnic identity. Your atypical trajectory could work for or against you. Nobody will accept you for a PhD program for “diversity”, unless you are considered qualified otherwise.
Diversity may cause them to select a certain qualified applicant as opposed to another equally qualified applicant. Sometimes there is some extra money so that they can accept a qualified minority applicant in addition to the ones for which their department has funding. Yes - PhD students cost money, so the number of students that are accepted each year depends on how much money a department or an individual faculty member happens to have.
A PhD is not required if you are a public policy expert and want to teach as an adjunct.
Unless you require a PhD to do the job that you want to do, there is no reason for you to do a PhD. A PhD is the least cost effective degree out there.