"early today" starts right now >>> good morning i'm melissa rehberger. >> and i'm phillip mena. the nation has now had the chance to hear from 20 of the crowded field of democratic candidates front runner joe biden took center stage, dominating the microphone he had the mose.speaking tim kamala harris and bernie sanders were close behind. one of the candidates who spoke the least was authoraryann williamson, but she was also the most searched for candidate on google >> biden and harris were the most tweeted about candidates up on stage and twitter reports that the most tweeted wout momentas when those two had a passionate exchange on the issue of race. for more insight on this, let's go to nbc's sarah miami following all this for us.ni good morng things got pretty heated out there. >> reporter: yes, they did, melissa. this was really one of the most dratic moments of last night this debate, of course, marking one of the first times in this race so far that we have seen the candidates begin to criticize one another. priously they had been reserving that for the current administra