Democratic senator Elizabeth Warren has announced she is formally preparing to campaign for president in 2020.
Mrs Warren, 69, released a video on Monday saying she was establishing a presidential campaign exploratory committee – typically the first step in a US presidential candidate's bid.
"In our country, if you work hard and play by the rules, you ought to be able to take care of yourself and the people you love," said Mrs Warren.
"No matter where you live in America or no matter where your family came from in the world, you deserve a path to opportunity.
"That's the America I am fighting for, and that is why today I am launching an exploratory committee for president."
Formerly a professor of law at Harvard, the Massachusetts senator is considered to be on the liberal wing of the Democrat Party.
In 2012, it came to light that Mrs Warren had claimed to be part Native American when she was teaching at the University of Texas and the University of Pennsylvania.
She had been mocked as "Pocahontas" by Donald Trump due to her claims of Native American ancestry at an event celebrating Native American war veterans.
At the time, Mrs Warren told MSNBC: "This was supposed to be an event to honour heroes, people who put it all on the line for our country, who, because of their incredible work, saved the lives of countless Americans and our allies.
"It is deeply unfortunate that the president of the United States cannot even make it through a ceremony honouring these heroes without having to throw out a racial slur."