After a few years focusing on issues such as electoral prediction through social media data, many analysts turned their attention toward fake news spreading and misinformation. A coherent next step in elections research through social media data would be identifying what makes communities and individuals less open to manipulation. Misinformation is not simply bad or false information but selective information circulated among isolated and unconnected groups. Here, I will discuss common cognitive biases in link sharing behavior and its effects on politically shaped communities in the Twitter public debate on the 2019 Spanish general election campaign. Finally, I will present and discuss some data-driven mechanisms that may contribute to the mitigation of mass manipulation.