The Hill 
March 2, 2012
About 18 percent of social media users have blocked, unfriended or hidden someone because of political material the person posted online, a study  released Monday by the Pew Center found.
Users said they cut off contact with someone if that person posted too frequently about politics, posted something offensive or argued about politics online.
People usually block distant friends or acquaintances, not close friends or family members. But about a third of those who have cut off social media contact with a person over politics say they have ended contact with a close friend or family member.