It has been represented by Democrat Rachel Zenzinger since 2017, following her defeat of incumbent Republican Laura Woods.

[3][4] District 19 is based in Denver's northwestern suburbs in Jefferson County, covering most of Arvada and parts of Westminster.

[6] Colorado state senators are elected to staggered four-year terms; under normal circumstances, the 19th district holds elections in presidential years.

In 2013, incumbent Democrat Evie Hudak chose to resign rather than face a recall election, and her former campaign manager Rachel Zenzinger was appointed to her seat.

[9] The resignation triggered an off-cycle election in 2014 which Zenzinger lost to Laura Woods.