Transcript for Fight to the finish in Texas as voters decide fate of red state

Texas could also make history tomorrow night, incumbent senator Ted Cruz challenged by Democrat Beto O'rourke. Look at this number tonight. More than 4.8 million Texans have voted early in this midterm. That's more than the total number that voted in the last midterm. ABC's Paula Faris is in Texas tonight. Reporter: Tonight, it's a fight to the finish in Texas, as voters decide if this deep red state will turn purple. The two senate candidates both in their 40s, one ran for president, the other could run one day. Senator Ted Cruz and three-time congressman Beto O'rourke could not be more different. Overnight, we were with Cruz in his final push. You look at the Texas economy right now. The economy is booming. We've got the lowest unemployment rate in 49 years. And I think Texans understand, why would we want to screw that up? Reporter: And Beto O'rourke with a new ad, traveling to all 254 counties, documenting it on his iPhone. This our chance, Texas, to lead this country. America has never been more divided, never been more polarized. Reporter: More people have already voted than the total that voted in the last midterm. Do you think that early voter momentum is leaning your way? I do. Reporter: And with president trump focused on the images of the caravan, so is Cruz. Security is on the ballot tomorrow. Reporter: You say you want to secure the borders, can you do that without a wall, can you do that without militarizing the border? We don't need a wall. We don't need to militarize the border. Reporter: O'rourke says we need immigration reform. It is precisely at that moment that Texas stands up, not as Democrats, not as Republicans, but as Americans, as human beings, to rewrit this country immigration laws in our own image. Paula, we know that Beto O'rourke is from El Paso. He likes to talk about the safety of El Paso, with all this talk of the caravans. Reporter: That's right, David. And the Mexican border is just a half mile from where we are. O'rourke tells me that the city of El Paso has been one of the safest cities in 20 years. As for senator Cruz, he's making his closing arguments tonight, David, a main theme will be border security. David? All right, big race in Texas, Paula. We'll see you tomorrow night here.

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