We know that because both candidates are working overtime to drive their supporters to the polls.
"The single biggest challenge we have is complacency," said Republican Sen. Ted Cruz at a recent rally. He told supporters they need to vote and ask the same of their family and friends.
"Now we need to finish the job," Cruz said.
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The one-term incumbent reiterated that sentiment during an interview with Eyewitness News.
"I do think there's no doubt this is a real race," he said. "This is a fight because the hard left is energized and you underestimate anger as a political motivator at your peril."
This is the same race Cruz won by 16 points six years ago. It is also not the same race. The political climate has shifted.
Also, his Democratic opponent, El Paso Congressman Beto O'Rourke, has out-raised Cruz significantly. He is getting both cash and media attention from places outside of Texas.
"This one is on us," the three-term member of Congress said at a rally in Corpus Christi. "No one is going to come to the rescue."
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O'Rourke is looking to build a coalition of support that transcends party affiliation. Texas is a red state. There are more registered Republicans than Democrats.
This spring, Democrats had their highest number of voters in a midterm primary since 1994. It was nearly double four years ago but still lagged behind the GOP turnout by a half million voters.
O'Rourke has his work cut out for him despite the energy and turnout at his rallies, but he remains optimistic.
"This campaign being run without PACs, being run without special interests or corporations, all people all the time makes anything that we want to do possible," he said in an interview with Eyewitness News. "We're bringing together everyone. We've been to all 254 counties, Republicans and Democrats alike welcome us at every single one of these meetings," O'Rourke said.
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Cruz knows that if he turns out his base, he may not win by 16, but he will win. That remains the biggest challenge, though.
"The danger is not, I believe, that a bunch of Texas conservatives are going to wake up and vote Democrat," he said. "I don't think that's likely to happen. The danger is just that folks stay home."
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