SUGAR LAND — U.S. Sen. Ted Cruz denounced the man who killed at least 11 people at a Pittsburgh synagogue Saturday morning, calling him a "cowardly, bigoted racist" at a campaign rally in the Houston suburbs.

In an interview with reporters after a stump speech in Sugar Land, the Houston Republican, who is being challenged by El Paso Congressman Beto O'Rourke, discussed the need for civility in the wake of disturbing acts of violence.

"This lunatic who murdered people today in the Tree of Life Synagogue was carrying out an act of evil," he said. "Evil doesn't have partisan allegiance. There are murders on both sides of the political aisle. Violence is wrong wherever it comes from."

At campaign stops in Dallas County, O'Rourke sought not to assign blame for the shooting but asked potential voters to unify behind values that define what it means to be American.

"The violence visited upon those congregants, upon the police officers who rushed into harm's way, risking their lives, willing to lose them, to protect the lives of others ... shows what's at stake right now in what is the world's greatest democracy," O'Rourke said at a campaign stop in Oak Cliff with Dallas Mayor Mike Rawlings and U.S. Reps. Eddie Bernice Johnson of Dallas and Marc Veasey of Fort Worth.

O'Rourke has said that elected leaders should do more than offer "thoughts and prayers" to victims of gun violence. He supports universal and more extensive background checks, raising the age to purchase guns, a ban on assault weapons and other measures.

Cruz has said he opposes universal background checks for gun purchases, but this year he re-introduced legislation with Sen. Chuck Grassley, R-Iowa, that they say would fix the broken background check system.

At Lake Cliff Park on Saturday, O'Rourke also talked about toning down the intense division that permeates American politics.

"It shows what we have to do to make sure that we continue to peacefully and nonviolently resolve our differences, find consensus, compromise when we can, so that we can do better for everyone," O'Rourke said of the shooting. "To see each and every one of us as Americans before we see each other as Republicans or Democrats, to find the common ground and the common cause so that we can achieve the common good."

In Sugar Land, Cruz used himself as an example of civility in politics and referred to three CNN debates he participated in last year with U.S. Sen. Bernie Sanders, a Vermont Democrat.

He said the two have diametrically opposite political views but managed to keep the peace.

"Both of us treated each other with respect and civility; that's an example I wish more in political life would follow," he said.

Cruz also said the most disturbing rage and fury was coming from the "extreme left."

"We know the hard left, they're angry, they're filled with rage and fury and many of them hatred for President Trump," he said in his speech.

He said liberals have a more "widespread" anger. But he acknowledged that last week high-profile Democrats, including the Clintons and President Barack Obama, were targeted with pipe bombs in the mail.

"That's one nut case who is a criminal and attempted murderer," he said.

With a week and a half left until the election, Cruz circled his home turf Saturday, riling up Republicans in Sugar Land and Katy.

While in Sugar Land, he reminded voters to support Congressman Pete Olson, who is facing an increasingly competitive race in the Houston-area district against Democrat Sri Preston Kulkarni.

Olson and Cruz warned voters not to get complacent, reminding Republicans that O'Rourke has broken fundraising records and is outraising and spending Cruz by a margin of 3 to 1.

"But the good news is that this is Texas," Cruz told the crowds, confidently asserting that Texas has more Republican voters than Democrats.

He made a pitch for voters to encourage their friends and family to get to the polls.

"I want each of you to vote for me 10 times," he joked, explaining that he means he wants people to bring nine friends. "I'm not the Democrats; I'm not encouraging voter fraud."

Cruz's rallies drew a couple hundred people at each venue.

Denise Garcia, who works at an engineering and construction company in Sugar Land, said she was a Democrat for 30 years. But she became a Republican when she started working for a company that intersects with the oil and gas industry.

"Immigration and all that stuff Beto is talking about, that's not the main focus," she said. "The most important thing is for Texas to keep the economy going and to continue to thrive."

Cruz told reporters he was encouraged by early voting numbers so far, which have exceeded numbers for the 2016 presidential election in many counties.

"I always say, if Texans show up and vote, we'll have a good election," he said. "And Texans are showing up."