Yes, you just create a script that goes to that portal, goes to the first portal row, pauses (e.g. fraction of a second) and goes to the next portal and loops to the end. You could set it at the end to scroll back up or to go to the top of the portal or whatever you wanted.
Keep in mind that all this time a script is running and the user is not going to be able to interact with the rest of the interface without escaping or hitting the script cancel button. But if you just want this for display, it would work ok.
Do you think clicking scroll bar is 'smooth' enough ?