-No poli sci degree (I have a degree in bio w/ some behavior)
-Skill/talent, but lack marketable experience.
-Never interned for consulting firm
-Some sales and marketing experience
-Political volunteer work (campaigns)
-A few friends with political jobs, but marginal influence
-Writing ability. Knowledge of skills I could offer.
You have the right experience. Marketing and campaign experience are valuable tools. So is writing.
The next step is to be visibly involved at the local level. Spend time with the Ward Commiteeman. Run for Local office or better yet, con a friend into running for office and manage his campaign. Become a precinct Captain. You don't have to win, just run an effective enough campaign to get noticed.
Write speeches for anyone who'll take them and network with as many folks as you can. It's not what you know. And it's only Who you know to the extent to which you can introduce people who are useful to people who can be useful to you.
There's more to it than that. But that'll set you on the right path.