Story highlights Rep. Tulsi Gabbard appeared in an emotional ad for Bernie Sanders' presidential bid

Gabbard quit her post as a DNC vice chairwoman when she endorsed Sanders last month

(CNN) Rep. Tulsi Gabbard, who has endorsed Bernie Sanders' presidential bid, appears in an emotional new ad for the Vermont senator, talking about her military service and why she believes he is the best choice for the next Commander-in-Chief.

The ad, titled "The Cost of War," features Gabbard, a Democrat from Hawaii who served a 12-month tour in Iraq, discussing why she decided to join the military and praising Sanders' foreign policy.

Replete with images of Gabbard surfing in Hawaii and accompanied by shots of the island and its residents, the ad is a big assist from a popular home-state representative and rising star in the party, ahead of the Democratic caucuses in Hawaii that take place Saturday.

"I felt a sense of duty and I could not in good conscience stay back here in beautiful Hawaii and watch my brothers and sisters in uniform go off to combat," she says of her decision to enlist in the 90-second spot.

A visibly emotional Gabbard chokes up and continues, "These are people and friends who we never forget, and who we strive to honor every day that we are blessed to live and breathe."

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