Washington CNN  — 

Jeb Bush is managing expectations for his struggling campaign’s performance in the crucial New Hampshire primary, conceding that “(Donald) Trump’s the front-runner and there’s a jump ball for second with five candidates.”

Bush sought to tamp down speculation about where he would finish in the Granite State primary and expressed cautious optimism in an interview with the Washington Post published late Wednesday.

“I think we have the best volunteers with the greatest commitment and greatest record, and get the candidate a little better, I think we’ll be in good shape,” Bush said when asked about his chances of finishing second.

“That’s irony, it’s a new concept in political life,” Bush quipped. “I just want to make sure you knew what it was when I used it.”

Bush, locked in a tight competition in the state for No. 2 behind Trump with New Jersey Gov. Chris Christie and Ohio Gov. John Kasich, also tried to distinguish himself from the other executives.

“My broad point is that my record, I think, is the one that, if you compare the three governors, in spite of their talents, is the best one,” he said.

During a New Hampshire town hall on Wednesday night, Bush also responded to a question from a Trump supporter who asked why the former Florida governor had tagged the businessman “a jerk.”

“When anybody, anybody, disparages people with disabilities, it sets me off,” Bush said. “That’s why I called him a jerk, because he disparaged a person who he knew had a disability and made fun of him. What kind of person would you want to have in the presidency that does that? Do you want a president that disparages women, Muslims of all kinds, people with disabilities, Hispanics?”

That’s like 90% of the population, Bush joked.

Bush said leadership requires “someone who has a completely different approach, someone who has a servant’s heart, someone who doesn’t think it’s about them, someone who has a proven record, someone who knows what he doesn’t know.”

CNN’s Ashley Killough contributed to this report.