Transcript for Democrats Meet in Final Debate Before the Iowa Caucuses
Back here now to the race to the white house, the battle lines hardening tonight. The language getting nasty as well. Donald Trump calling Ted Cruz just that, saying no one even likes him. And the friendly glow also now missing from Hillary Clinton and Bernie sanders as the candidates in the democratic race get set to debate tonight. ABC's Cecilia Vega is there tonight. Reporter: Tonight, all that feuding on the campaign trail comes to a head in south Carolina. Thank you. Reporter: For Hillary Clinton whose popularity runs deep. A palmetto state standing ovation. But the democratic socialist from Vermont played to a tougher crowd. Audible gasps when Bernie sanders' 30-minute speech seemed to go too long. This morning on "This week" the heated war of words hotter than ever. Clinton railing against sanders on gun control. He flip-flopped last night said that he would sign on to a bill. Reporter: Sanders firing back. It disappoints me that the Clinton camp is kind of sounding like republicans. Hello, everybody! Reporter: Across the aisle, former friends Donald Trump and Ted Cruz now in a nasty rivalry. He's a nasty guy. Nobody likes him. Nobody in congress likes him. Nobody likes him anywhere. Reporter: In a new ad Cruz standing by those controversial New York citlues remarks and digging into the vault with this shot at his billionaire rival. I'm very pro-choice. And again, it may be a little bit of a New York background because there is some different attitude in different parts of the country. Reporter: Cruz's supporters defending their candidate booing the Donald Trump this weekend. Excuse me, didn't report his bank loans, say whatever you want, he didn't report bank loans, that's okay. Reporter: But trump not backing down. You're saying he's a hypocrite? Oh, he's a total hypocrite. Reporter: As for that democratic debate, before the Iowa caucuses, just two weeks away, both the Clinton and the sanders' campaign bracing for each side not to hold back tonight. Tom, everything is on the line out there. Cecilia, thank you.
This transcript has been automatically generated and may not be 100% accurate.