IMHO no incumbent should be allowed to campaign. They were elected to do a job and if they are off campaigning they are not doing the job. If they are worth a grain of salt they should be able to use the success they have achieved while in office and the voters could use that standard to decide if they want this candidate to continue to represent them. If a incumbent wants to run for a different office than he or she holds at the present time then they need to make a very simple choice. Either forget about the different office or resign so someone else can do the work they were elected to do. Campaigning for a better job while getting paid for not doing the job you were elected to do (sometimes for more than two years) just makes my decision of who I am going to vote for very, very easy.