Prior to redistricting the district was represented by Democrats Kevin Priola (who was elected twice as a Republican before switching parties) and Mary Hodge.

[3][4] District 25 is based in eastern Adams County in the suburbs of Denver, including parts of Thornton, Brighton, Bennett, Todd Creek, Strasburg, and the northern reaches of Aurora.

[6] Colorado state senators are elected to staggered four-year terms.

The old 25th district held elections in presidential years, but the new district drawn following the 2020 Census will hold elections in midterm years, starting in 2022.

Incumbent Republican Senator Kevin Priola was redistricted to the 13th district, which won't be up until 2024.