They would have to sever many long-term business ties such as board directorships and probably miss out on a lot of lucrative investment opportunities to avoid conflicts of interest.
You don't honestly believe this?
There are a lot of intelligent, successful people in America who will not run for Congress precisely because it would wreak financial havoc on their lives.
You really don't believe this. Bill Gates is highly intelligent and it wouldn't cost him a penny to become a Congressman and he doesn't seem to want the job. There are people who aren't even paying their child support that are Congressmen and there are fabulously wealthy people who don't need to work at all to support themselves who refuse to be Congressmen. Either you are a political animal or you're not. We only need a few hundred Congressman and 100 senators. In a country of 330 million I'm sure there are some pretty good hearted smart people that can do the job for more money than 94% of the country makes.