So, obviously, you will have to have some luck on your side. You'll have to become governor in a state that permits that describe above, and then you need a senator to get out of your way and give you that seat. But success, as Ben Franklin said, is when preparedness meets opportunity. And as Jefferson said, "I am great believer in good luck—the harder I work, the more of it I have." You have to work your way into the governor's position in a "good" state, so never forget that!
Most important through all this is that you always find a way to point the finger at someone else. You have to use sleight of hand like a master magician, getting people and, especially, any government investigators to look in another direction while you go about your underhanded business. Manipulate the media like a fine orchestra conductor. Tell lies with a calm demeanor and a straight face, feigning a slight amount of indignation that you would even be suspected of anything illegal or nefarious; be sure that you have your lies memorized so that as you tell them over and over and over again, they become ever more believable. Remember, if you tell a lie over and over again often enough, the masses of people will believe it. "Wasn't me" should become your tag line.
But your real effort is to avoid being accused or even suspected if you possibly can. It will help you to get elected as a democratic governor in this regard. You can invoke the "vast right wing conspiracy" if you even get questioned about what somebody else heard somebody else say about you, and the mainstream media will lap that up, in their lust to accuse republicans of doing every wrong thing that democrats do routinely. The democrats have professional political sales machinery in place that republicans can't even fantasize about, so even if you really vote for the GOP don't run on their ticket. Switch political party's midstream if you need to, and say that it's all because you don't like the direction in which the GOP is headed and you know that people desire to pay more and bigger taxes.
No matter what, stay off the telephones, look the other way for your double-dealing lobbyists, take a break from taxing the people, and tell everyone at every opportunity how clean you are. Selling your senate seat is hard work!