Dealing properly with the presence of ironic devices is indeed crucial when the goal is to analyze the polarity of the opinions on a topic of interest, and in political domains irony is very often used in conjunction with a seemingly positive statement, to reflect a negative one, due to a phenomenon known in literature as polarity reversal (Bosco et al., 2013).
the issue has to be tackled in order to correctly label the polarity of an opinion, going beyond the literal meaning of the posts.