Pew Research Center:

Among social media users, Democrats – and liberal Democrats in particular – are a bit more likely than Republicans to say they have ever modified their views on a social or political issue, or on a particular political candidate, because of something they saw on social media. (Democrats and Republicans include independents and nonpartisans who “lean” toward these parties.)…

…the majority of social media users are not swayed by what they see in their networks. Some 82% of social media users say they have never modified their views on a particular candidate – and 79% say they have never changed their views on a social or political issue – because of something they saw on social media.