The two Texas Republican candidates for a U.S. Senate seat locked horns in a Friday night televised debate, but displayed few policy differences.

When asked directly if there "is anything your opponent has done that shows he lacks the integrity and character that these voters say they want," both Lt. Gov. David Dewhurst and former state Solicitor General Ted Cruz said that question would be decided by voters, who can choose between them in a July 31 runoff election for the GOP nomination.

"I'm not here to criticize my opponent," Dewhurst replied.

But before the moderators had even posed the next question, their fists were up again.

"I'll leave the judgment of character to the voters," Cruz said to the integrity question, adding that the election was a choice between his record "and the lieutenant governor's record of serving in elected office for over a decade, repeatedly compromising with democrats, increasing spending, increasing taxes."

"I find it amusing the lieutenant governor said he is not here to attack me, given he has spent over ten million dollars of his own money running false nasty attack ads," he continued.

Dewhurst fired back: "I'm not going to respond to the fact that you have your Washington insiders, and you have all these Washington special interests that have spent millions and millions of dollars saying untrue things about me. I'm not going to go there."

But by saying that, the issue was raised.

As if the fireworks needed more fuel, the candidates were next invited to directly ask one another a question.

"You have been widely criticized for posing a statewide wage tax," Cruz began. "Your response is to call your critics liars. So I have a very simple question: did you support a payroll tax, and is that a good idea?"

Dewhurst retorted, "No and no."

"That's very interesting," Cruz returned.

Given his chance to pose a question of Cruz, Dewhurst listed his own military and intelligence service, then asked, "What about your background is, do you think, makes you more qualified to be the next U.S. Senator?"

Cruz commended Dewhurst's service, and cited his own time "fighting for the constitution and winning on the national level" as a lawyer.

The race has been as expensive as the debate was nasty. Through early May, Dewhurst and allies spent more than $17 million to Cruz and his allies' $4.3 million, according to the most recent Federal Election Commission records available.

The runoff came after no candidate locked down the GOP nomination in a May primary. Sen. Kay Bailey Hutchinson, a Republican, said in January 2011 that she would not seek reelection.

Cruz and Dewhurst largely agreed on the role of the U.S. military, immigration policy, immigration, and reforming social security. Each also vowed to propose a repeal of the health care law signed by President Barack Obama on his first day in office.

The similarities were so noticeable that the moderators' last question was "could you give us a brief example of how Senator Dewhurst would vote differently on an issue than Senator Cruz?"

That question brought out some of the few compliments the two exchanged.

Dewhurst said of Cruz, "I believe him to be a conservative," then touted the business-oriented frame through which he views problems.

Cruz allowed Dewhurst "is a good and decent man," but continued that his opponent has spent 15 years in elected office as a "conciliator."

The two are expected to debate again in July before the runoff election at month's end. Two democratic candidates, former state Rep. Paul Sadler and campaign strategist Sean Hubbard, will debate next month, the moderators said, although a Democrat has not represented Texas in the senate in over 20 years.

The race has attracted national interest and competing endorsements from within the Republican Party. Former presidential candidate Rick Santorum and former Alaska Gov. Sarah Palin, as well as some tea party organizations, have endorsed Cruz. Gov. Rick Perry has sided with his lieutenant, and Dewhurst is also backed by former Arkansas Gov. Mike Huckabee.

After Friday's debate curtain fell, the jabs continued.

Cruz charged that Perry's backing of Dewhurst isn't genuine support, but an effort to boot him from the state capital.

According to the Fort Worth Star-Telegram, Cruz told reporters at a post debate press conference, "It is in his political interest to get rid of David Dewhurst and get him out of Austin and send him somewhere else."

Dewhurst, however, did not speak to reporters.