The 2018 elections were the first midterm elections since 2002 in which the party holding the presidency gained Senate seats.[1] Republicans defeated Democratic incumbents in Indiana, Missouri, North Dakota and Florida. Democrats defeated the Republican incumbent in Nevada and picked up an open seat in Arizona. All four defeated Democratic incumbents represented states won by Trump in the 2016 presidential election.[2] Democratic incumbents tallied victories in the competitive Midwestern states of Ohio, Michigan and Wisconsin as well as the key Northeastern swing state of Pennsylvania.[20] Montana and West Virginia, each of which voted for Trump by a margin of at least 20 points, also re-elected Democratic incumbents.[21] After the election, Chris Cillizza of CNN noted that by limiting their Senate losses in 2018 Democrats put themselves in position to potentially take control of the Senate in the 2020 or 2022 Senate elections.[5]