CONCORD, N.H. — Mitt Romney’s strategy of targeting his Republican rivals may have finally succeeded in ruffling at least one, Michael Huckabee.

Mr. Romney jumped right out of the gate at a GOP debate last night in attacking his top competitors on tax-and-spend issues, and he accused the usually quick-witted Mr. Huckabee in particular of dodging the truth.

“You make up facts faster than you talk, and that’s saying something,” Mr. Romney told Mr. Huckabee as they sat side-by-side in a Fox News forum.

The two were debating their respective records as governors, in which they have repeatedly tried to fend off the criticism that they resorted to tax hikes to close budget gaps and fund new spending.

Mr. Huckabee, a former Arkansas governor, appeared uncomfortable in the intimate and free-wheeling format that Fox set up last night. He and Mr. Romney, who served as governor of Massachusetts, were seated literally elbow-to-elbow at the center of a table, and Mr. Romney used the arrangement to needle Mr. Huckabee on the issues, asking him direct questions that proved impossible to ignore.

At the outset, Mr. Romney tried three times to get Mr. Huckabee to admit that although he both raised and lowered various taxes in Arkansas, the result was a net increase of about $500 million. “Now, I asked you a question to begin with. And that was, net-net, did you raise taxes in your state by half a billion dollars?” Mr. Romney asked. Mr. Huckabee tried to deflect the question. “We raised jobs. We built roads,” he began, before Mr. Romney cut him off: “You know, that’s political speak.”

Mr. Romney tried the same tactic later in the debate when the topic turned to immigration. Mr. Huckabee has defended his support as governor of giving in-state college tuition breaks to the children of illegal immigrants, saying children should not be punished for the crimes of their parents. But he has proposed an immigration plan as a candidate that would require all illegal immigrants to return to their home country before applying for legal status or face deportation, meaning those same children could be forced to separate from their parents or leave America.

“How about the kids in school, them, too, or not?” Mr. Romney asked him, nudging his arm.

Mr. Huckabee tried again to ignore him. “Mitt, I’m talking to Chris right now, if you don’t mind,” he responded, referring to the moderator, Christopher Wallace.

Mr. Wallace chose to ask him the same question, and Mr. Huckabee said most parents would not leave without their children, with the possible exception of high school seniors who might be old enough to fend for themselves.

For Mr. Huckabee, the exchanges were rare moments of awkwardness and discomfort for a candidate who has thrived on his folksy appeal and good humor. He is coming off a momentous win in the Iowa caucuses last week, but despite a modest bump in the polls, he remains in third place in New Hampshire, well behind Mr. Romney and the leader, Senator McCain.

A CNN/WMUR poll released yesterday showed Mr. McCain of Arizona with 32% support, Mr. Romney at 26%, Mr. Huckabee at 14%, and Mayor Giuliani at 11%.

Last night’s debate was the second in as many nights for the Republicans, and Mr. Romney showed he was unbowed by the barrage of barbs and attacks that came his way on Saturday night, mostly focused on his reputation as a flip-flopper and his steady stream of negative television ads.

Mr. Romney has built his campaign based on the goal of winning the early primaries, and losses in both Iowa and New Hampshire could be devastating to his hopes.

In addition to attacking Mr. Huckabee, he also accused Mr. McCain of supporting “amnesty” for illegal immigrants and criticized him over his opposition to President Bush’s tax cuts.

In a lighter moment, Mr. McCain, who will be 72 in 2009, also refused to pledge that he would only serve one term, saying that would make him an immediate lame duck. “You’re going to be quacking on Inauguration Day,” he quipped.

Notably excluded from the debate was Rep. Ron Paul, the antiwar Texas congressman who finished well ahead of Mr. Giuliani in Iowa and is statistically tied with him in New Hampshire and well ahead of another participant, Fred Thompson. Mr. Paul protested his exclusion and held a separate town-hall forum.