Transcript for Sen. Amy Klobuchar throws hat into presidential race

the candidates who want to take on president trump in 2020. The list growing. Two major names officially I announcing over the weekend, and quickly taking aim at the president. Here's ABC's Mary Bruce. Reporter: In the middle of a Minnesota snowstorm -- We don't let a little snow stop us. Reporter: -- Senator Amy klobuchar promising her mod rat politics and mid western roofts will win over key states that handed Donald Trump the white house. I don't have a political machine. I don't come from money. But what I do have is this -- I have grit. Reporter: On "Good morning America," klobuchar asked about recent reports she's a touch boss. What do you think is fair about that criticism and what have you learned from it? Well, first of all, iy staff. I am tough, I push people, that is true. But my point is, is that I have high expectations for myself, I have high expectations for the people that work for me, and I have high expectations for this country. Reporter: In Massachusetts, senator Elizabeth Warren made it official this weekend with a call to action. Start asking the people who have gained the most from our country to pay their fair share. Reporter: She's already tangling with trump. By the time we get to 2020, Donald Trump may not even be president. He may not even be a free person. Reporter: Five women in congress are now running. One of them, senator kamala Harris, discussing her support for legaliing marijuana and giving an answer that was once considered controversial. Have you ever smoked? I have. Okay. And I inhale -- I did inhale. Okay. It was a long time ago. But yes. Listen, I think that it gives a lot of people joy and we need more joy. We need more joy in this world. And Mary Bruce with us live from Washington. A lot of eyes on former vice president Joe Biden, waiting for word from him whether he will run, and something new on his schedule tonight? Reporter: Biden says he's still running the traps on this, and will have an announcement soon. There's a new event on his schedule this month is being billed as a discussion on the future of American politics. We'll be listening closely. Wewill. Mary, thank you.

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