It's a bit more complicated than that. The devs make polls sometimes on the Patreon page. This provides a few insights, but nothing totally conclusive.
For example, back in march, before Season 3 ended, there was a poll about choosing between six characters the ones you wanted more content with. Here are the results : Dakota 554 votes, Haley 477, Ashley 371, Samantha 310, Grace 222 and Gabriella 137.
Dakota had the lead and Haley was second, probably because lots of people want more content with Dakota while Haley has been there since the beginning. So, there is a strong Haley following, no surprise here, and players want more of her, but apparently also want something new, involving Dakota.
Note that there are no global polls involving ALL characters, only polls with characters being roughly in the same "category"(there is another poll involving MILF characters, for example, with Victoria and Sabrina at the lead, and a third one for the new students appearing in season 3, led by June and Eva). We could compare votes, and discover that Victoria got the most compared to everyone in every poll (585 votes), but since there has been no global poll, yet, it's difficult to make something from that.
Also, some characters were left out of the polls, likely because their place in the storyline changed (Lily for example) and they're no longer around to fool with, or because the devs and the most contributing patreons - who have additional voting power - talked about them in the backroom and felt they had to be set aside.