Republican Tom Cotton, likely the next Congressman from Arkansas’ 4th district, encountered an older woman with a tough question for him early in his campaign.

“Why would you want to leave the country’s most respected institution, the Army,” he recalled her asking, “and go to the country’s least respected institution, the Congress?”

The answer is rooted in what happened 11 years ago, while Cotton was sitting in Professor Charles Nesson’s Evidence class at Harvard Law School.

“I walked out and there were dozens, if not hundreds, of people standing around in shock and grief and sadness and tears. I asked what was going on and they said the World Trade Centers were under attack,” Cotton recalled. “And I walked over to the student commons and it was just in time to see the first tower go down.”

Though the Sept. 11 attacks made Cotton want to join the Army immediately, he finished law school first, did a clerkship with a judge and worked at a firm. Once he had paid off his law school loans, he signed up to be an officer in the infantry and shipped out to begin training in January 2005.

“The main reason I’m running is a lot of the same reasons I left my law practice to join the Army,” he said. “I think the country is at a crossroads and we need new and young leaders who are willing to step forward and make some hard choices that are going to help put the country back on the path to security and prosperity.”

After serving almost five years in the Army, with tours in Iraq and Afghanistan, Cotton is now the GOP nominee in a strongly Republican district in a state that has been trending more conservative. With the retirement of Rep. Mike Ross (D), the open seat is quite likely to be represented by Cotton come January.

Political operatives in the state say Cotton, 35, has a profile that’s unusual among aspiring Razorback State officials.

“He presents himself differently than your traditional charismatic Arkansas politician,” said one state GOP strategist, who repeatedly used the word “intellectual” to describe Cotton’s campaign demeanor. “He’s 6 [foot], 5 [inches]. He’s not your chubby politician running around. He’s not what we’ve always seen. He’s young, he’s fresh, he’s different, he’s new.”

If his résumé is unique, his talking points on the trail are familiar. In an interview Friday, Cotton said his campaign rhetoric won’t change now that he’s in the general election.

“Fighting to repeal Obamacare, to reform our tax code and lower our tax rates, to get the debt crisis under control and finally confront it and to keep America strong in the world and safe at home,” he said when asked the reasons he is running.

National and state Republicans expect him to be an outsized presence on Capitol Hill, with many GOP operatives already using the “rising star” label to describe him.

The Democratic Congressional Campaign Committee has a different set of epithets. A press release recently called him a “Washington insider” and slammed his “completely out of touch” agenda.

Cotton has been endorsed by the powerful anti-tax Club for Growth, the conservative website RedState.com, Citizens United and Sen. John McCain (R-Ariz.).

He will face the winner of a Democratic runoff — either attorney Q. Byrum Hurst or state Sen. Gene Jeffress — in the general election.

Fellow Arkansas GOP Rep. Tim Griffin, a JAG officer in the Army Reserves, said he first met Cotton in person at Fort Campbell, Ky., when they were both preparing to ship out to Iraq.

Griffin praised Cotton’s political acumen and his discipline on the campaign trail. He expects Cotton not only to easily win, but to become a Congressman who leads.

“He’ll be a high-energy Member,” Griffin said. “I think he’s someone who is going to be a force from day one. The sky’s the limit for him down the road.”