DALLAS (CBSDFW.COM) – Democratic Congressman Beto O’Rourke rallied a standing room only crowd of 1,700 supporters at the Good Street Baptist Church, the only church in Dallas where Dr. Martin Luther King once spoke.

On Friday night, O’Rourke expressed outrage about the deadly shooting of Botham Jean by a Dallas police officer.

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“What is released to the public? That he had a small amount of marijuana in his kitchen,” said O’Rourke. “How can that be just in this country? How can we continue to lose the lives of unarmed black men in the United States of America at the hands of white police officers? That is not justice. That is not us. That can and must change. Are you with me?”

O’Rourke’s visit comes days after a CBS-11/Dixie Strategies poll shows him trailing Republican Senator Ted Cruz by four points.

CBS11 asked him how he intends to jump ahead in the race and stay there through the election.

“My money and all of my faith is on the people of Texas,” O’Rourke told the crowd. “I don’t know that the polls that show us a point down, three points down fully represent everyone who’s coming out right now.”

Beto O’Rourke at South Dallas town hall (CBS11)

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SMU political science professor Cal Jillson says to win, O’Rourke needs to keep doing what he’s doing, but he says he will need some Republicans to join independents to cross over, which he considers unlikely.

“There’d have to be 15 percent voters or so who do that and that’s a lot of voters who aren’t taking the easy way out which is vote a straight ticket and leave,” Jillson said.

Professor Jillson says by the first of October, O’Rourke needs to jump ahead of Cruz in the polls by three to six points to withstand numerous Republican TV ads.

O’Rourke supporter Stanley Pounders said, “Yes, he’s got a chance. Look at the people here. Look at the exposure. This hasn’t happened before, I showed up and I hadn’t done it before.”

Rep. O’Rourke and Sen. Cruz. will participate in three mutually agreed upon debates leading up to the 2018 U.S. Senate election in Texas, the O’Rourke campaign confirmed on Friday.

The debates will happen in Dallas on September 21, Houston on September 30 and San Antonio on October 16.

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The topics will be domestic policy and foreign policy.