In 2018, Isgro faced a recall election after he made a Twitter post mocking David Hogg, a survivor of the Stoneman Douglas High School shooting in Parkland, Florida. The recall effort was backed by former Mayor Karen Heck, a Democrat who had previously endorsed Isgro. Isgro later made his Twitter feed private and said that he had deleted the post. During the recall effort, Isgro asserted that outside interests and the City Council were plotting to oust him over disputes over the city budget and taxation. After an acrimonious recall campaign, Waterville voters narrowly defeated the recall attempt, with 1,563 "no" votes (51%) to 1,472 "yes" votes (49%).