(CNN) Progressive activist and organizer Alison Hartson announced Thursday she is joining the race to challenge Democratic California Sen. Dianne Feinstein.

Hartson made it official during an appearance on "The Young Turks" online news show. She enters the state's increasingly crowded open primary contest with the backing of The Young Turks host and founder Cenk Uygur, his progressive media network and a political group he co-founded, the Justice Democrats.

"California needs a bold progressive to lead the way and this particular race, in 2018, is going to be one of the most if not the most important race, in 2018, in the country and that's because California has the sixth largest economy in the world and what we do does, in fact, influence the country," Hartson said during an interview with Uygur, who announced he will act as a campaign adviser.

I am proud to run with @justicedems to challenge Corporate incumbent @SenFeinstein to represent the state of California. pic.twitter.com/6tADogG9as — Alison Hartson (@Alison_Hartson) November 2, 2017

"We're coming -- we're coming at 100 miles an hour," Uygur said. "This will not be a normal campaign ... when you find out how conservative Dianne Feinstein is, it is unconscionable that she is our senator in California."

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