What is the starting salary of a politician?

This really depends on what you mean by politician. Do you mean representative, senator, etc. Also, what state?

Right now, the President of the United States is paid $400,000 per annum, plus expenses. Understand that in his case, "expenses" will be many times the actual salary.

On the other hand, local politicians often serve for free, or for a tiny salary that doesn't cover their expenses.

On the "third" hand, you have extreme examples, like the recently fired city manager out in some small town in California who was knocking down over $800,000 a year. I think even the police chief was making more than the POTUS.

I think it's correct to say that the salaries of politicians varies tremendously, based on a number of factors. Where I live, township trustees serve in exchange for payment of about $150/month, but it's a small township with a small population. In other locations, a township trustee or a politician in a similar position could actually make a living doing nothing else.