Transcript for Republican Power Couple?
works out for investors. Thank you. And now to the race for 2016, trump with his biggest lead in New Hampshire. And tonight, Sarah Palin on the stump for Donald Trump and talking about the arrest of her son. Reporter: Donald Trump is used to driving the news cycle but today Sarah Palin took the wheel. Our vets deserve a commander in chief who will let them do their job and go kick Isis' ass. Reporter: Mamma grizzly echoing her roaring endorsement for the republican frontrunner. Are you ready to make America great again? Reporter: Giving her fans some of the greatest hits. So no, we're not going to chill. In fact, it's time to drill, baby, drill down and hold these folks accountable. Reporter: But today not everything going as planned. The trump campaign announcing Palin would be at a morning rally in Iowa. The tickets even promising a special guest. But no sign of Sarah. We were hoping Sarah Palin would be here. Reporter: And what happened, no show? No show. I was looking forward to seeing her. Wondering where she went. Reporter: And Palin's surprises didn't end there. Today in Tulsa, she brought up her 26-year-old son track's arrest this week for allegedly assaulting his girlfriend. It's kinf of the elephant in the room. Reporter: Police say track, a veteran, threatened to shoot himself with an ar-15 assault weapon. Palin revealing her son is coping with PTSD. Saying vets wonder if the president knows what they're going though. My son, like so many others, they come back a bit different. They come back hardened. I can certainly relate with other families who kind of feel these ramifications of some PTSD and some of the woundedness that our soldiers do return with. Reporter: The politician turned reality star. You can see Russia from here, almost! Reporter: Now helping the reality star turned politician. You're fired. Reporter: Trump grateful though he hedged when pressed on whether he'd pick Palin as his running mate. Well, I don't think she'd want to do it. I don't think she'd want to do it. You know, I really don't get into it right now. I don't even think about vp right now and I just want to win. Reporter: Putting on a brave face, trump's chief rival, senator Ted Cruz. I love Sarah Palin. Reporter: Cruz's answer to the Palin endorsement, two rallies Saturday with conservative firebrand Glenn beck. And this ad -- Cruz in camo hunting with reality superstar Phil Robertson, from "Duck dynasty." Ted Cruz is my man, he fits the bill, he's the man for the job and he will go duck hunting. And Tom llamas with us. Last night, it was a Iowa governor seeming to warn against Ted Cruz. And tonight, bob dole with tough words aimed at Cruz as well? Reporter: That's right. Saying Cruz is an extremist, and saying if he's the nominee, the losses for the republican party would be cataclysmic. Saying he would pick trump over Cruz any day. David? Tom llamas, thank you. On the democratic side, it was just hours before Hillary
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