Transcript for Former Starbucks CEO considering 2020 presidential run?

In the meantime, the race for 2020, the list of candidates who want to take on president trump is growing tonight. The former CEO of Starbucks, Howard Schultz, signaling overnight he might reason. Tonight, the reaction has been swift. And over the weekend, 20,000 turning out for senator kamala Harris. Here's ABC's Mary Bruce. Reporter: Democrats warn he could cost them the white house. But former Starbucks CEO Howard Schultz isn't backing down. If I run for president, I will run as an American, under one banner, the American flag. Reporter: Schultz, a lifelong Democrat, would run as an indepent. Both parties are consistently not doing what's necessary on behalf of the American people. Reporter: But former New York major Michael Bloomberg, who considered an independent run himself, insists "An independent would just split the anti-Trump vote and end up re-electing the president." The democratic field is already getting crowded. California senator kamala Harris kicked off her campaign this weekend before a crowd of more than 20,000 people. We must answer a fundamental question. Who are we? Who are we as Americans? So, let's answer that question to the world and each other right here and right now. America, we are better than this. Hard to believe that we're talking about another presidential election. Mary with us live tonight. There was a headline involving Hillary Clinton this weekend a report that she hasn't closed the door completely on another run, but our team has confirmed that this doesn't mean there's a campaign in waiting. Reporter: David, Hillary Clinton is not readying another run. Now, she has not ruled it out explicitly and she did say she would like to be president, but so far, there are zero signs that she's going to give this another go. David? All right, Mary Bruce live with us tonight. Thank you.

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