Dianne Feinstein was agitated.

The Democratic senator from California did not like the line of questioning she was getting from Sen. Ted Cruz, the freshman Republican from Texas, as she defended her so-called assault weapons bill before the Senate Judiciary Committee in March.

Cruz was reciting from the Constitution. He then asked that given Feinstein’s position on the government banning certain types of guns: Would she also approve of the government banning books it found harmful?

“I’m not a sixth grader,” Feinstein responded, expressing contempt for the question. She went on to point out that she had “studied the Constitution myself,” and “am reasonably well-educated.”

“I thank you for the lecture,” she added.

The heated debate between the two senators was significant. Cruz now admits he thinks his aggressive questioning helped draw negative attention to the bill, stopping it from ever having a serious chance of passing.

It also illustrates the kind of first-term senator Cruz has become. In his first 100 days on Capitol Hill, Cruz has been tireless in trying to shape the political debate in the Senate, from guns to Obamacare to drones to Defense Secretary Chuck Hagel’s nomination hearings.

In an interview with The Daily Caller last week, Cruz said, “My focus every day in office has been on two things. Number one, defending the Constitution. And number two, fighting to restore economic growth.”

Cruz’s outspokenness has not gone unnoticed by his colleagues.

“He’s been right in the middle of almost every major debate we’ve had,” Mitch McConnell, the Republican leader in the Senate, told TheDC in an interview. “And that’s pretty unusual for somebody who just arrived and was just sworn in.”

Speaking by phone, McConnell said of Cruz: “He’s a force. Already.”

Asked if the 42-year-old Cruz is more outspoken than the typical freshman lawmaker, the leader said there’s “no question.”

“I say that with admiration,” McConnell said. “Now others, some people are saying that with a different connotation. I think he was fully prepared intellectually and temperamentally to hit the ground running and not, you know, be intimidated by the place. And I think that’s something to be admired.”

As his encounter with Feinstein indicates, the former Texas solicitor general is fond of talking about the country’s founding documents.

“Ted is one of these guys you can ask about any provision in the Constitution and he can recite it for you almost verbatim,” Utah Republican Sen. Mike Lee said.

With all of his activity, Cruz is developing a national fan base of conservatives. He keynotes national conservative confabs, like the Conservative Political Action Conference. He is also comfortable taking the conservative message to the Sunday shows, once battling New York Democratic Sen. Chuck Schumer on “Meet the Press.”

His supporters argue he can help improve the Republican Party’s image with youthful vigor, humor and a positive message. He often speaks of what he calls “opportunity conservatism.”

Former Alaska Gov. Sarah Palin tells TheDC she is a fan, praising Cruz for playing an active role as a freshman senator and not bowing to the tradition of being a quiet first-term legislator.

“As the world is seemingly spinning faster and faster, and the political decisions coming out of Washington affect the entire globe, the LAST thing we need today is an intelligent, experienced, patriotic commonsense conservative ‘be seen and not heard,’” Palin said.

“America needs leaders like Senator Cruz to be bold and effective, as there’s no time to lose in getting our nation on the right track to ensure our solvency and safety,” she said. “More power to Ted Cruz and others who are serving the people for the right reasons.”

Cruz spoke to TheDC about what he considers his early achievements.

On Second Amendment rights, Cruz said it is “certainly one area where we have seen tangible results because of our concerted effort to focus on the facts and the substance and the Constitution.”

Last week, the Senate voted down a number of pro-gun control amendments, including Feinstein’s assault weapons ban. (The body also voted down alternative gun legislation offered by Cruz).

Cruz said he’s also proud of his questioning of the Obama administration’s drone policy, after Kentucky Republican Sen. Rand Paul led a filibuster on the issue.

“We saw significant success with the White House [and] forced [it] to do what it had refused to do for weeks, namely to admit in writing that there is no constitutional authority to kill a U.S. citizen on U.S. soil if that individual doesn’t pose an imminent threat,” he said.

The Republican has also continued the fight against President Obama’s health care law, introducing amendments this year to defund and repeal Obamacare altogether.

“Initially, when I stated that I was going to introduce those amendments, there was significant opposition within the Republican conference to doing so,” Cruz said. “And yet, both times, when the vote came to floor, we held every single Republican, all 45 senators voted to defund and to repeal Obamacare.”

Earlier this year, Cruz made news for his aggressive questioning of the new defense secretary during the secretary’s confirmation hearings.

“I played an active role focusing on his foreign policy record,” Cruz said of Hagel. “And aspects of it that were well out of mainstream. And we were able to hold 41 Republican votes on a filibuster to delay consideration of that nomination, to spend more time focusing on aspects of that record.”

As for the next big issue, observers are waiting to see what role Cruz will play in the debate on immigration reform.

“I think the key to actually getting legislation passed that addresses our broken immigration system is for Congress to focus on areas of widespread, bipartisan agreement,” Cruz said. “If, instead, the focus of the legislation is on legislation of sharp, sharp, partisan disagreement and, in particular, if the focus is on providing a pathway to citizenship for those who are here illegally, I think that is likely to scuttle the bill.”

Some old timers in the Senate have publicly criticized Cruz for his outspokenness, especially after the Hagel hearings.

Liberals have predictably pounced on Cruz. Last week, Washington Post opinion writer Dana Milbank even asked in his column, “Is there nobody who can tell Ted Cruz to shut up?”

But his allies in Congress argue the press he has attracted for his tense encounters during Senate hearings has given a false impression of the man. He gets along well with members of both parties, they say.

“He’s got a very collegial approach,” Lee of Utah said. “He’s got a very collegial manner that’s evident to anybody that gets to know him. And it’s different than the caricature, the heavily caricatured image, portrayed by some in the media.”

“One side of Ted people don’t talk about is he’s actually good company too,” said McConnell. “I took him to Afghanistan, along with a couple of other freshman back in January. You learn a lot about somebody if you spend a lot of time with them over a short period of time. He’s got a great sense of humor. Great company. Whip smart.”

Cruz says that despite his ardent feelings on issues, he never resorts to personal attacks against his opponents.

“There have been some attacks leveled my way,” Cruz said. “And I have consistently declined to reciprocate or to speak ill of any other senator but instead to stay focused on the substance.”

The Texas senator has a grueling schedule, returning to Texas every weekend, where his wife and children live. Over the Easter recess, he traveled around the state, speaking to Chamber of Commerce luncheons and Republican galas.

Asked about all the chatter about his political style, Cruz said he’s just doing what he campaigned to do.

“I have to say Washington is an unusual place,” he said. “Because they seem very, very surprised when you come here and do what you said you were going to do.”

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