TUCSON — Does Rep. Ron Barber have the sheer force of will to win re-election?

“I want it as bad as I’ve wanted anything in my life,” said the Arizona Democrat, who was first sworn into office in June 2012.

Barber, 68, is in the race of his life. He's among the nation's most vulnerable Democrats, representing a seat that leans Republican in a midterm battle that will likely feature lower turnout than when President Obama was on the ballot in 2012. In that election, he squeaked by with a 0.8 percentage point win.

Beyond his district's GOP tilt, he's dealing with whispered doubts about his motivation and health.

On a Saturday morning in 2011, the sound of gunfire cut through the usual chatter outside a Safeway in Tucson. Jared Lee Loughner, the gunman, had fired into the crowd at Rep. Gabrielle Giffords, who was holding a "Congress on Your Corner" event. The shooting left six dead and more than a dozen wounded.

Barber, who would replace Giffords after her resignation, was shot twice, in the face and thigh. Later, in 2012, he had minor surgery to remove a cancerous tumor from his tongue.

Republicans are not using his motivation as a criticism, either in public or in private. But among friendly Democrats who want him to succeed, there is concern about Barber’s stamina, and whether he truly wants the job.

The criticism comes wrapped as a compliment. Supporters say Barber, who never sought office before running for Congress, does not relish the spotlight or the prestige of the job. He’s a ‘West Wing’ politician – smart, hard-working, likable – but he lacks the ferocity that characterizes many ambitious politicians. After the emotional and physical drain of the last few years, doubters say, maybe he just doesn’t have what it takes to make his case for another term.

It’s the conventional knock against Barber. Arizona Democratic congressional aides, campaign staffers and candidates all mentioned it – off the record, of course.

Upon meeting the twice-wounded lawmaker in person, these doubts subside.

Fresh off a visit to Afghanistan, he sat down with the Washington Examiner in his favorite neighborhood restaurant, speaking animatedly and intimately about border security, deportations, high-tech industry in his district and his political philosophy.

After the interview time was up, he insisted on staying longer to answer questions until there were no more. And he addressed the doubts about his motivation, dismissing them as old news. Barber recalled that in 2012, blogs were being “snarky” about the prospect of his election.

“A few of them said, ‘how can this old guy, who has been wounded twice, possibly win an election, let alone serve in Congress?’” he remembered. He won a special election in 2012, then another election later that year.

Barber concluded, “Well, this old guy who has been wounded twice is more energized than I ever have been!”