New technology and SM outlets influence nearly everything in our modern world that's why finally, politicians can use SM as a cheap and efficient way to sway a person's vote.
For example, if someone's excited about a politician and they have a strong SM presence, this only further excites the already positive voter. In contrast, someone with a negative view on a politician sees constant positive reinforcements throughout their SM feed from followers they know and trust are more likely to change their mind and be more open to a candidate.
Overall, politicians shouldn't want to be on SM sites... They should view it as a critical part of their campaign.