MY PREDICTION:
First of all the mangaka will draw out this "battle" for various chapters, we won't know who "won" for awhile.
Secondly, Ruka will win, but it's going to be a lot closer than we imagined.
Lastly, despite the fact that Ruka wins, nothing will change, Hayate will still be Nagi's Butler and I believe something will happen to make Ruka "go away".....I don't mean this in a negative way, I just mean she won't be featured in the manga as a main character anymore.
Overall, whether I'm right or wrong, I'm just dying for this "arc" or whatever the hell you call this to be resoved.
I swear to god, I feel like it's been 100 chapters since they've been on this doujinshi battle.