Mr Bush, the front-runner for his party's nomination, had elicited taunts from the other candidates for his refusal to take part in two previous candidates' debates. He accepted the invitation for last night's event only after his closest challenger, Senator John McCain, drew even with him in the polls in this state, which will stage the second, and key, primary election in two months' time.
A new poll out yesterday indicated that Mr Bush, who holds a commanding lead in every other state, was also ahead in New Hampshire.
Mr Bush spent much of the week with his advisers, preparing to convince viewers that he could hold his own, and to banish the impression that he lacks gravitas and rose to prominence thanks to family connections and money.
But with 90 minutes between all the candidates, yesterday's forum turned out to be more of a talk show than a debate.