Politicians should be held to a different standard, and a different (more restrictive) set of laws. Politicians sell influence/access. If you want to stamp political corruption, remove the politician's ability to trade on this influence.

Here are a few ideas:
IF a politician leaves office and wants to work in the private sector, he/she should have to wait, say, 2 years. Many politicians leave office and then get paid exorbitant sums as a partner at a private equity fund, for example. They have no expertise in investing capital, so why are they being paid millions of dollars by an investment firm? Connections. Sever this link.
IF you get paid for speeches, you shouldn't be able to run for office (I'm taking to you Hillary).
IF you have a spouse who holds political office, you shouldn't be able to give speeches for money.
You shouldn't be able to sit on any boards or be paid to sit on a board for 4 years after you leave office.
You shouldn't be able to raise money for your non-profit for 4 years after you've left office.

Just tossing out some ideas.