David Axelrod--Man Of A Thousand Descriptions

On Saturday's Nightly News, two separate promos for "Meet The Press" included graphics that described David Axelrod as a Senior White House "Adviser". On Sunday's and Monday's broadcasts, excerpts from Axelrod's MTP appearance described him as a "White House Senior Advisor". Is he an adviser or an advisor? It is unbelievable (and unbelievably sloppy) that the Nightly News producers continue to use these two spellings interchangeably--sometimes on the same broadcast. For goodness' sake, could they please pick a spelling and stick with it?