Retired army general Don Bolduc, a Republican, on Wednesday announced that the Hawaiian congresswoman would be appearing alongside him on the campaign trail.
“We don't agree on every issue, but I am honoured to have the support of Tulsi Gabbard who shares my view that the status quo is broken, and we need a change of direction,” Mr Bolduc said.
“Tulsi is a fellow change agent and independent-minded outsider willing to speak truth to power.”
Ms Gabbard on Tuesday announced her departure from the Democratic Party, which in a blog post she called “under the complete control of an elitist cabal of warmongers driven by cowardly wokeness”.
Speaking on right-wing television host Tucker Carlson's Fox News programme, Ms Gabbard said the Democratic party is actively undermining “our God-given rights enshrined in the Constitution like freedom of speech”.
“The list goes on and on, but the foundation of freedom is really what was at the heart of my making of this decision that I cannot be a member of a party that is against freedom and actively trying to undermine it,” she said.
Ms Gabbard accused the party of being “anti-woman”, weaponising law enforcement and using federal agencies to target conservative groups.
She also accused President Joe Biden's administration of bringing the US to the edge of nuclear warfare.
Ms Gabbard, who sought the 2020 Democratic nomination for president, became the first American Samoan and Hindu to be elected to Congress in 2012. A veteran of the war in Iraq, Ms Gabbard characterised herself as a non-interventionist against “wasteful regime change wars”.
Also a critic of the Democratic party's “open border” policies, Ms Gabbard during the campaign trail also claimed that Washington's intervention in Latin America caused the migration movements along the southern US border.
Ms Gabbard's views, which are seemingly more concurrent with conservative ideologies, made her an outsider in Democratic circles. Earlier this year, she spoke at the Conservative Political Action Conference, a convention that typically features the most prominent voices within the Republican party.
Hillary Clinton, who secured the party's nomination for president in 2016, even suggested that the former Hawaiian congresswoman was a “Russian asset”. Ms Gabbard filed a lawsuit against Ms Clinton but soon withdrew it.