This poll is obviously trash, but I have a hunch that actual office holders with fundraising and GOTV networks and connections to the local machine are going to have an easier time than some local news anchor.
Why would somebody do better than in their own internal poll?
Usually, the purpose of an internal poll is to create a particular narrative for a particular race, especially if posted publically. It's not impossible for a candidate that the internal is done for to perform better in a poll that's not an internal.