Democrats have not held the state Senate since 2014 and aimed at flipping it to potentially achieve a political trifecta as Democrats were expected to retain control of the state House and gubernatorial nominee Jared Polis was considered the frontrunner heading up to the polls.

Democratic women dubbed the "Fab Five" were running to defend or win these five competitive districts.

[4][5] Source:[6][7] Seven incumbent senators (three Democrats, three Republicans and one independent) are term-limited and unable to seek a third term.

Most of the votes that led to the Senate flipping was due to the outsized margins Democratic candidates received throughout the Front Range and ski counties.

[10] The results in the Senate and other elections throughout 2018 were called by observers a "blue wave" in which Democrats made historic gains in Colorado.