Transcript for Hillary Clinton Calls Most GOP Candidates 'Trump Without the Pizzazz or Hair'
we hope. The race for president and a brand-new poll showing Hillary Clinton losing altitude as she interrupts her vacation for a trip to Iowa. Striking out at the gop adm admitting mistakes in how she handled the e-mail controversy and speaking out for the first time on a possible challenge from Joe Biden. ABC's Cecilia Vega was there for all of it. She joins us now from des Moines. Good morning, Cecilia. Reporter: George, good morning to you. That's right from those e-mails to Donald Trump and everyone else running against her on the right but when it comes to one of America's hottest political debates Hillary Clinton had a one-liner. Things getting a little hairy for Hillary Clinton on the trail in Iowa. Most of the other republican candidates are just trump without the pizazz or the hair. Reporter: The democratic front-runner joking about Donald Trump but when it came to those e-mails this time it was no laughing matter. I'm confident that this process will prove that I never sent nor received any -- any e-mail that was marked classify. Reporter: And issued a mea culpa about the scandal that plagues her campaign. It clearly wasn't the best choice. I should have used two e-mails, one personal, one for work and I take responsibility for that decision. Reporter: But when it comes to Joe Biden's decision to run against her, Clinton says it is his to make. I think he has to make what is a very difficult decision for himself and his family and he should have the space. Reporter: Biden speaking to party leaders during a conference call Wednesday says he's still undecided following the death of his son beau in may saying if I were to announce to run, I have to be able to commit to all of you that I would be able to give it my whole heart and my whole soul and right now both are pretty well banged up. And that new poll will probably have Biden pretty happy and Hillary Clinton pretty worried. Take a look at these Numbers I want to show you. There's Hillary Clinton right there with 45% her lowest Numbers so far this campaign, followed by Vermont senator Bernie sanders and Biden with 18% who is not even in the race and could wait until October to decide whether to run or not. Hillary Clinton losing altitude in that same poll and Donald Trump flying even higher. Reporter: That's right. I want to show you those Numbers too. Donald Trump so far ahead of the pack with 28%, his highest Numbers so far. His biggest lead too followed by Dr. Ben Carson and you can see trailing with 7% bush and Rubio. Packed up. Cecilia Vega, thanks very much.
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