The genius of democracy
The genius of democracy is a lot like that of capitalism: You can't get rid of ambitious loons, and if you did, the ambitious loons next door would move in and helotize you. So you harness them. You provide them with a relatively safe and convenient path to advancement, and you arrange it so they'll benefit everybody by getting ahead (in the case of capitalism), or, in the case of democracy, they'll at least do somewhat less damage than they otherwise would.
If you don't let people gain wealth or power more or less honestly, they'll do it as dishonestly as they must. Remember the Soviet Union?
The key is understanding that neither democracy nor capitalism is perfect, nor is intended to be. We have merely struck a deal with these people to get them more or less off our backs. Though if it gets to be too much less, with those clowns in DC, we may have to hang a few to encourage the others.