Transcript for More than 30 million Americans have cast early votes

campaign talkers as voters get ready to cast their ballots in these midterm elections. And large crowds are already lining up to vote early. ABC's white house correspondent Tara Palmeri has more. Reporter: This morning, early voting for the midterm elections is shattering records. More than 30 million people have already cast votes as of November 2nd. At this point four years ago, just 17 million people had already voted. Celebrities making the late push like Leonardo Dicaprio and Brad Pitt unveiling last-minute ads about what's at stake. All of these races and ballot measures are a chance to decide on the direction of our country. Hello! Reporter: Even Oprah out in Georgia campaigning for Democrat Stacey Abrams. Hi, Oprah. How are you? Reporter: If elected Abrams would be the first black woman to hold the office of governor. There are a record number of women running. 16 on the ballot for governor, 237 for the house and 23 for the senate. The turnout on track to make history. At least 4 million people have already voted in Texas, surpassing the state's total turnout in 2014. In the battleground state of Florida, Democrats and Republicans are casting their ballots at nearly equal rates. The president on a final campaign blitz and feeling optimistic. If your party loses the house, will you change your agenda we're going to see. I think we're doing well. Certainly we're doing very well on the senate, and I think we'll also do well in the house. We'll see. Reporter: Just a few hours later the president was already changing his tune admitting for the first time in a rally in West Virginia that the Republicans could lose the house. Dan. That's a really interesting admission. Tara Palmeri, thank you for joining us from the white house. Joining us now in the flesh ABC news chief political analyst Matthew dowd. Great to see you. Great to be here. Usually you're via satellite. From Wimberley, Texas. A hot state in terms of the campaign right now. You just heard Donald Trump said for the first time apparently that it's possible the Republicans could lose the house. That's what the polls are indicating. The polls also indicate the Republicans are likely to retain the senate, however, in 2016 the polls were not super reliable in some ways. So what should we believe? Yeah, I said in 2016 that Hillary Clinton had a 90% chance of being president of the united States, so we know how that goes. First of all, they should watch ABC news on Tuesday. That's the first thing people should do. I think the thing to pay attention to in 2016 the national polls were right. They basically said Hillary would win the popular vote and she won the popular vote. So those were right. I think state by state and district by state we have no idea. And as Tara just said, the early voting is setting all kinds of records. Texas, where I just came from, has already voted more people early than voted in the entire election in 2014 and all the numbers that are up seem to be among young voters, Latino voters, and women are setting records so I think it's going to be a long night. I don't think we'll know for sure. But nobody has any idea how to set a model for this type of election turnout. So just to put a fine point on this, we do have models show it's likely but not guaranteed the Republicans keep the senate. The Democrats take the house but you're saying anything goes. Well, anything goes because I think that because of this turnout that we're seeing it -- we could be off in many, many different polls by 3%, 4%, 5%. Very quickly, the president has these new economic numbers. Really impressive economic numbers that he can justifiably tout, and yet he seems to be putting most of his emphasis on the caravan. Why do you think that is? He has the best economy going in the first midterm in 60 years and they're not talking about it. I think this president goes to rallies and understands when he talks about the economy, his crowd doesn't get all ginned up. When he talks about immigration and when he talks about the caravan and the Democrats, they get very excited and the reason is we talked about it earlier is immigration is the number one issue for Republicans. It's not among all voters but among Republicans it is and so I think the president is going to keep pushing this. I think he thinks fear is more of a motivator than success in this. I disagree with this because I think this election is going to be decided by independent voters who have decided all the elections in the last 25 years and independent voters I think would be much more key to say, oh, yeah, the economy is going well. Why should we change things but this president has appealed to his base since he got into office since his inaugural address and has done it every single day and doesn't seem to be giving up on it in the last 72 hours. Always great to see you. Great to be here. Excellent, and we should say as Matt said, be sure to join us for full coverage on election night. George Stephanopoulos, our chief anchor, will anchor and he'll be joined by our team including Matt and David Muir and others at 8:00 eastern right here on ABC. Matt, thanks again. Great to be here.

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