In the last decade, social networks have emerged as a significant media platform for dissemination of political information. In this article, we characterize linguistic factors that affect the dissemination of a political message on Twitter. This is important because characterization of messages that were posted by users from both political camps can provide a unique insight into how rival audiences can be reached. We analyze about 20,000 Twitter users who expressed explicit support for Barack Obama or Mitt Romney during the 2012 U.S. presidential election. We extracted approximately 344,000 tweets by these users that contained links to political webpages and appeared in the 3 months prior to the election. We show that the language used in a linked page is correlated with the page’s popularity in terms of the total number of users that post a link to this page. Pages that are written in a more Republican language are posted by a larger number of users than Democrat-leaning pages. We also observe that pages that use highly polarized language are generally posted by users from a single political camp. Pages that are reposted by both Romney and Obama supporters are usually written in a relatively neutral language. In addition, when the user is a Republican, the text accompanying a retweeted page is likely to be modified, usually to refute information that conflicts with the user’s viewpoint.