I thought the Kevin Spacey series was pretty good, though dated. You wouldn't expect a White South Carolinian to have much influence in today's Democratic Party, though that was certainly true of the Democrats in earlier decades. One thing about the series is that we kind of feel like we know Washington goings-on, so really outrageous plot lines might be hard to believe (or maybe not, considering what it is that we actually do know about Washington).
Boss with Kelsey Grammar was also over-the-top in some of its intrigues, but it's easier to believe that a mayor of Chicago would get away with some really outrageous acts than that a congressman could. Plus, sometimes you can get tired of Spacey's archness and irony and want to go for something more straightforward. I miss Boss. If you like House of Cards, you might give it a try.
Then there's Borgen from Denmark, about a woman prime minister ...
I think a SC Democrat could be a big player - the libs love to hide liberalism in a southern accent. Al Gore. John Edwards, Bill Clinton, etc. BUT BUT ….it would be a Charleston Democrat, or maybe a downtown Columbia Democrat - from one of the bohemian sections of those two cities..(and both have them, especially Charleston).
Underwood is no upstate SC candidate….
Dobbs, the writer of the original books, was actually a Conservative Party big wig before becoming an author. A lot of people he dealt with informed the character.
Remember since FU is a whip his power comes from secrets. Skin color and place of origin don’t really play into that, just ability to fix problems and hold them over people later. That’s really the essence of the story, the guy who is the most powerful secret person in the country wanting to become publicly powerful.