Transcript for Elizabeth Warren reveals proof of Native American ancestry
But Toles says he hopes she will be left in peace. Linsey, thank you. A major headline that could involve a candidate for 2020. Elizabeth Warren said she will give serious thought to a run in 2020. President trump, who calls her pocahontas, said he would pay $1 million to a charity if she proves her native American heritage. Here's Mary Bruce. Reporter: His opponents say it's a racial slur, but president trump relishes his nickname for senator Elizabeth Warren. They call her pocahontas. Pocahontas. Reporter: Trump seizing on Warren's claim that she is part native American. Even once leveling this challenge. I will give you $1 million dollars to your favorite charity, paid for by trump, if you take the test and it shows you're an Indian. Reporter: Trump claims that Warren used her heritage to help her get ahead. But there is no evidence it advanced her career. Still, today, the Massachusetts senator, who is eyeing a 2020 white house run, took up the president's challenge, releasing this video showing her receiving the results of a DNA test. What do the facts say? The facts suggest that you absolutely have a native American ancestor in your pedigree. Okay. Reporter: Warren was told she had a native American ancestor in the range of six to ten generations ago. But tonight, the president is scoffing at the results. How much? 0.001%? She owes the country an apology. What is the percentage? 0.001%? Reporter: As for that million dollar offer -- I will only do it if I can test her personally. Okay, that will not be something that I enjoy doing either. Mary, Elizabeth Warren said she will decide about running for president after the midterms, but it seems like she's seriously considering it. Reporter: The timing leaves no one with much doubt. But Democrats say they wish she would have waited until after
This transcript has been automatically generated and may not be 100% accurate.