It's really just a DM call, but I would say that unless you had the spell running every time you were out in public (which should be a lot if you're looking for a sidekick) it wouldn't have any effect.
Also, since the efforts will continue for several days, I would only take the average bonus into consideration.
Finally, if you let down the spell after you get the cohort or followers, they would realize that you aren't as prestigious as your ads claim and leave.
So, while it might work to an extent, lots of luck trying to do it effectively.