Johansen sat in the municipal council of Munkebo Municipality from 1997 to 2006, and served as deputy mayor from 2001 to 2006. In 2006 the municipality was merged with Kerteminde and Langeskov Municipality to form a new Kerteminde Municipality. He sat in this new municipality's municipal council from 2006 to 2011.[1]
Johansen was first elected into parliament in the 2011 election. He was reelected in 2015 and 2019.[2]