I know a few politicians covering the three levels (both sides of the fence). None well enough I can say I know all about them, but a few that I have had a number of dealings with, and usually when the cameras aren't around.
From my experience, most get into politics for genuine reasons. Some are extremely passionate about their job and the people they represent and they work 7 days a week in order to do so. Others, not so much.
Whilst the pay is pretty good, for me, its not good enough to put up with the shit that comes with it
With the budget, i'm still trying to find out where one can get a burger and milkshake for ten bucks!