I don’t think it means that he has a history as an actual politician. I think it means that everyone has a political history — I do, you do, etc. — what his past political ideas and affiliations have been.
Yours and my political history is on a firmer ground than that of a Billionaire international businessman. You and me go by what agenda we desire and stick to it. A large business operates to make a profit, in a fiercely competitive real world main street economy. Therefore the business decisions are made purely from a business point of view. That includes contributing to whichever politician with the power to throw obstacles in your business. Those decisions may not have any connection to what the business owner really favors as his agenda. That would put him/her out of business very fast.