Transcript for Democratic presidential candidates battle for Iowa
reconsider his request for witnesses over the holidays. Tom? Rachel, thank you. Now to the race for 2020, and the front-runner fight in Iowa. Pete buttigieg getting an appearance from Kevin Costner. Most of the candidates cris-crossing the states. And Mike Bloomberg has a different strategy. Here's Stephanie Ramos. Reporter: Tonight, democratic candidates for president blitzing the hawkeye state, fighting for front-runner status the Iowa caucus just weeks away. Mayor Pete buttigieg taking heat at the last debate. I can't help but feel that might have been directed at me. Senator. Senator, I've got to respond to that. Reporter: Clashing with senator Elizabeth Warren over closed door fund-raisers. The mayor just recently had a fund-raiser that was held in a wine cave full of crystals. I'm the -- literally the only person on this stage who is not a millionaire or a billionaire. Reporter: Today in indianola, voters lining up to see the South Bend mayor. I just want to see Pete. This is my third event, I want to hear more of what he has to say. Reporter: Taking the stage with Kevin Costner. We need to bring everybody into this struggle. This campaign is calling out to Democrats who may have agreed with some of these things all along, to Progressives, to moderates. Reporter: Former vice president Joe Biden surprising caucus-goers at their home. At this rally, telling us his fellow candidates won't unite the party by attacking each other. I don't think it's a good thing. I think we got enough division in the party as well. Reporter: This week mayor Michael Bloomberg skipping Iowa entirely, opening offices across the country in key battleground states, in Pennsylvania, Wisconsin, and Michigan. I'm spending a lot of money. But my investment is to keep Donald Trump from being the president the next time. Reporter: The billionaire pledging to keep the offices open even if he's not the eventual nominee. Stephanie, live on the trail in Iowa. Michael Bloomberg making major financial plays all over the country. Showing he's committed to staying in. But that still won't help him make the debate in January. Reporter: That's absolutely right, Tom. Michael Bloomberg says he doesn't care about debates. The DNC is implementing stricter qualifying rules so candidates have to poll better, and have more donors than before. Just five candidates qualifying for the next debate. And as you can see, senator Cory booker has taken the stage here. He said his campaign is focused on Iowa voters right now. Tom? Stephanie, thank you. Now to tensions with north Korea. The U.S. Closely watching for
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