I don't mean PC agent's as in a faction you can dick around in and get acces to just like that. It should be very limited, an honor to join and above all well regulated.
Get people who don't rp to win and it should add a great immersive factor to the roleplay.
All factions overseen by DM's aside, this is something that is achievable with you at the head of it. As a player, you are granted the liberty to establish such groups as you so please, however, such groups would not draw respect from their simple title (at first) but rather the leader's tact and know how in the leading of individuals.
Consider this hypothetical:
As a denizen of these here mists, I get knocked on the head, I now and forever more begin to see a light. I come to this conclusion, that I am meant for a greater purpose and am now going to consider myself an "Illuminati!" Through my interactions I befriend players in already high places with deceit, honesty or any mixture of character and action and as I gain these friends and more I induct them into the Illuminati promising great riches and powers (Perhaps I was a cleric to begin with and draw my divine energy from the Dark Powers sating my delusions?) Nevertheless time goes on, I make few enemies and soon enough, my guy is pulling strings with his political ties with buddies in both strange and I places...
Now, achieving some sense of renown and coming out as the cult leader of the Illuminati may be possible, or perhaps I decide it is a secret soceity and have my highest echelon of puppets answer to me... How it plays out is truly dependent on the dynamics of the population at the time however you can probably predict how some of the more static personalities would react, such as Strahd, Azalin, Dominic d'Honaire, etc. but the point is it all started with you.
Say for another case, you don't want to be a cult leader:
As an aspiring entrepreneur and opportunist, I learn that people really enjoy their potions. I begin an agricultural business focused on the harvesting and studying of foliage about the Core. I put my plans in action and my fortune to use in paying the wages of employees and making deliveries where I may, I soon acquire a profit and come into a sustained measure of wealth. I have then successfully entered the rich socialite crowd. At the top of my game I get to make money doing very little in the ways of labor. I can now throw events to boost my prestige. I could commission players to write plays to honor me, a ballad for my love interest, or hire an assassin to strike at my nemesis. And once again, it all starts with you.
There are a plethora of ways to enter the political scene, and moreover a great number of ways to do so with the immediate tools at your disposal. The DM's play a more reactive role and in that stance they await you to make the first move -- ingame. If you kick up enough dust, who knows, Strahd might invite you into his castle for dinner and proposition.
Ways to help ensure that your character's motives and achievements have been noted, begin a journal in the
Biography section of the forum. DM's will be able to track your successes AND failures, as will other players get a kick out of a good read.
Anyways, I hope this helped to motivate a selection of some path to politics :3