Terje was first elected Chair of the Vermont Democratic Party in 2017 and was reelected in 2019. Before serving as Chair, Anderson served as a DNC Member from Vermont.

Terje has been a life-long advocate for people with AIDS -- serving as Executive Director for the National Association of People with AIDS. He has served as AIDS Program Chief for the Vermont Department of Health and was the founder of the Vermont Committee for AIDS Resources, Education, and Services. He has chaired the Health Resources and Services Administration's HIV/AIDS Committee and has been the co-chair for the National Organizations Responding to AIDS. In addition, he has also served as co-chair for the Vermont Coalition for Lesbian and Gay Rights.

Terje resides in Montgomery, Vermont with his dog Bronco.