Transcript for Elizabeth Warren on the Campaign Trail With Hillary Clinton
As we know, th benghazi attack a red-hot issue in the race for the white house, as Hillary Clinton hits the campaign trail with senator Elizabeth Warren. Warren attacking trump. Trurp wasting no time firing back. Cecilia Vega is here with the latest. Reporter: Good morning. Clinton and Warren joining forces to attack Donald Trump. Warren calling him a small, insecure, money-grubber. Those are fighting words. âª This is my fight song âª Reporter: After the hand-holding and the fist pumping. Now I'm here today because I'm with her. Yes. Her! Reporter: Came the insults launched at Donald Trump. You want to see goofy. Look at him in that hat. Reporter: Elizabeth Warren joining Hillary Clinton on the campaign trail for the first time, playing the role of attack dog in chief. When Donald Trump says he'll make America great, he means make it even greater for rich guys just like Donald Trump. Reporter: Will she join the ticket? I do just love to see how she gets under Donald Trump's thin skin. Reporter: ABC news has learned the Massachusetts senator is among the names being formally vetted as a possible Clinton running mate. Clinton herself not going there. How are you feeling at Elizabeth Warren as a vp pick? Are you lit was a great event. Reporter: Are you liking her for vp? I'm not making any news today. Reporter: Donald Trump is calling Warren a sellout and mocking her for claiming she's of native American descent. Pocahontas. Pocahontas. Pocahontas. Reporter: Calling her a fraud. Saying she made up her heritage. Former Massachusetts senator Scott brown jumping in, too. She can take a DNA test. Reporter: Clinton acknowledges she's still struggling to win over voters who just don't trust her. It certainly is true. I've made mistakes. So I understand people having questions. But -- I know trust has to be earned. Reporter: Okay. The big question this morning, will there be an all-female ticket? Warren certainly helps Clinton woo some of those Bernie sanders supporters. The Clinton campaign sees her as an asset when it comes to attacking Donald Trump. Some question whether the country is ready for to women on the same ticket.
This transcript has been automatically generated and may not be 100% accurate.