WASHINGTON (Reuters) - U.S. Democratic presidential front-runner Barack Obama got a close-up look at the sort of slash-and-burn politics he has vowed to rise above -- and he did not appear to like the view.

The Illinois senator grimaced in clear discomfort at times in Wednesday night’s debate as the spotlight shone on issues like Obama’s fiery pastor, his relationship with a 1960s radical, his remarks about small-town voters and his failure to wear a lapel flag pin.

The debate with Democratic rival Hillary Clinton gave Obama a chance to road test the responses he will need if he captures their party’s nomination and faces Republican John McCain in what promises to be a tough November presidential election.

“This was a test for Obama, and I don’t think he did particularly well. He is going to have to improve. He was clearly uncomfortable and looked a little pained by it all,” said Cal Jillson, a political analyst at Southern Methodist University in Texas.

“He needs to develop some smooth, confident answers to these issues because he’s going to hear plenty more of it,” he said.

Obama was grilled by ABC News moderators about the inflammatory tirades of his former pastor, the Rev. Jeremiah Wright, and about his characterization of small-town residents as clinging to religion and guns in bitterness over their economic struggles.

He also was asked about his failure to wear a flag pin in his lapel, a token of patriotism for some other politicians, and his relationship with William Ayers, a member of the violent leftist Weather Underground group in the 1960s and now a Chicago neighbor.

ABC came under fire for the questioning on Thursday. Washington Post television critic Tom Shales called it shoddy and despicable, while the liberal grassroots group MoveOn.org started an online protest petition.

At a rally in North Carolina, which votes on May 6, Obama said a discussion of health care, Iraq, jobs and gas prices took a backseat to the effort to fire up more controversy in the debate. He said Clinton seemed “in her element.”

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“I know some people were frustrated with last night but the truth is all that was happening was that was the rollout of the Republican campaign against me in November,” Obama said.

“It happened just a little bit early but that is what they will do. They will try to focus on all these issues that don’t have anything to do with how you are paying your bills at the end of the month,” he said.

The controversies have popped up in the Democratic presidential race during a seven-week lull between the last round of major contests in Ohio and Texas on March 4 and next week’s critical showdown in Pennsylvania.

MEDIA, NOT VOTER, INTEREST

Linda Fowler, a political analyst at Dartmouth College in New Hampshire, said the media were more interested than voters in the controversies. She said polls showed Obama’s small-town comments, which became public over the weekend, have had little impact.

“This says more about the media than about the candidates. If this stuff is so important, why aren’t the polls moving?” she said.

Clinton, the New York senator and former first lady who has faced her own campaign gaffes, was glad to join in the examination of Obama during the debate.

She tried to capitalize on Democratic paranoia about the Republican success in attacking the last two Democratic nominees, John Kerry and Al Gore, by arguing the issues Obama faced in the debate are the same type Republicans will try to exploit in November.

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“It goes to this larger set of concerns about how we are going to run against John McCain,” Clinton said in the debate. “I’ve been in this arena for a long time. I have a lot of baggage, and everybody has rummaged through it for years.”

Clinton faces a struggle trying to overtake Obama in the Democratic presidential race. She trails in delegates to the Denver nominating convention in August and needs a big win in Pennsylvania on Tuesday and a strong closing effort in the last nine contests to position herself to win the nomination.

While her campaign aides have frequently criticized the media for not subjecting Obama to as much scrutiny as Clinton has faced, they were clearly pleased with the debate grilling.

“In an ideal world, I wish we could conduct our campaigns on questions of policy and policy differentiation. We’ve learned that campaigns are about much more than that,” said Clinton spokesman Howard Wolfson.

“The questions that Senator Obama were asked last night are the kind of questions Senator Obama will face if he is our nominee,” he said.