positions make him "unfit" for holding a public office.
All set to become the first Senator of Indian-origin this year, Harris said, "Donald Trump is doubling down on his outrageous, dangerous rhetoric."
"Most recently, he called for a ban on all Muslim immigrants and accused Muslim American communities of hiding terrorists," Harris said in an email to her supporters.
Harris is running for the United States Senate from California, a Democratic bastion.
Herself being a Democrat and a close friend of US President Barack Obama, her victory in the November general elections is considered a foregone conclusion by political pundits.
In her email, Harris slammed Trump for his recent rhetoric.
"Just days before that, he claimed that a federal judge was biased against him, because of the judge's Mexican heritage," she said of the 69-year-old real estate tycoon.
"We already know that Trump's unstable temperament and dangerous policy positions make him unfit to hold any public office, but his latest comments make even more apparent Trump's racism and incompetence," Harris said.
"Trump can't see beyond race, gender, and religion -- and he doesn't want to -- not when it comes to the judiciary, not when it comes to women's health, and not when it comes to civil liberties," the 51-year-old said as she urged her supporters to join the anti-Trump campaign.
In latest polls, Harris is leading her nearest rival Loretta Sanchez by a massive 25 points.
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