WASHINGTON — Senator Clinton is warning that Senator Obama’s comments about small-town Americans make him vulnerable to the fate suffered by Vice President Gore and Senator Kerry: being labeled an out-of-touch elitist and losing to the Republicans.

The former first lady criticized Mr. Obama for a second straight day, saying his diagnosis that working-class voters were “bitter” was not only elitist but patronizing. She suggested the remarks were “in line” with the oft-repeated charge that the Democratic Party did not understand mainstream American culture and values.

“We had two very good men and men of faith run for president in 2000 and 2004,” Mrs. Clinton said at a forum on faith televised live on CNN last night. “But large segments of the electorate concluded that they did not really understand or relate to or frankly respect their ways of life.”

Mr. Obama appeared separately at the same event, which came at the end of two days of intensifying recriminations among the three presidential candidates following the publication of Mr. Obama’s comments on Friday by the Huffington Post.

He delivered the remarks April 6 at a private fund-raiser in San Francisco, when he sought to explain his struggle to appeal to blue-collar voters. He said small-town Americans in Pennsylvania and elsewhere have been frustrated by job losses under both Democratic and Republican presidents. “So it’s not surprising, then, that they get bitter, they cling to guns or religion or antipathy to people who aren’t like them or anti-immigrant sentiment or anti-trade sentiment as a way to explain their frustrations,” he said.

The Illinois senator defended himself at the CNN forum, emphasizing that he was a “devout Christian” and saying that while his wording may have been “clumsy,” he did not mean to offend religious voters. “What I was referring to is in no way demeaning to a faith that I myself embrace,” Mr. Obama said at the forum, held at Messiah College in Grantham, Pa. Both the Clinton and McCain campaigns have seized on Mr. Obama’s words in San Francisco, with Mrs. Clinton hoping that the flap will secure her standing with working class voters while causing undecided superdelegates to doubt the Illinois senator’s electability.

Though reserved at the CNN forum, Mr. Obama reacted to Mrs. Clinton’s criticism angrily at an earlier campaign stop, rebuking her for making political hay out of his comments.

“She knows better. Shame on her. Shame on her,” he said in Steelton, Pa., according to a transcript provided by his campaign. Mr. Obama mocked Mrs. Clinton for responding to his comments by citing her experiences hunting with her father as a child. “She is running around talking about how this is an insult to sportsmen, how she values the Second Amendment. She’s talking like she’s Annie Oakley,” Mr. Obama said, referring to the sharp-shooting title character of “Annie Get Your Gun.”

“Hillary Clinton is out there like she’s on the duck blind every Sunday. She’s packing a six-shooter. Come on, she knows better. That’s some politics being played by Hillary Clinton.”

A spokesman for Mrs. Clinton responded by saying that Mr. Obama had for months “relentlessly attacked Hillary Clinton’s character and integrity” by using Republican talking points. “The shame is his,” the spokesman, Phil Singer, said.

President Clinton also weighed in on the flap yesterday, recalling to Pennsylvania voters the words of a man he had just met backstage. “This fellow looked at me and he said, ‘I just want you to know, the people you’re about to see are not bitter. They’re proud,” Mr. Clinton said as the crowd clapped, NBC News reported. At the former president’s stops in North Carolina on Saturday, volunteers handed out stickers reading, “I’m not bitter,” the network reported.

Mr. Obama’s campaign worked feverishly to contain the damage throughout the weekend, sending out rapid rejoinders to Mrs. Clinton and Mr. McCain while highlighting favorable news coverage and punditry. Mr. Obama’s top supporter in Pennsylvania, Senator Casey, said on CNN’s “Late Edition” that the suggestion that Mr. Obama was elitist was “ridiculous.”

As the Clinton campaign pressed the case against Mr. Obama, reports surfaced of similar comments made by both Clintons to explain voter concerns about issues like religion, guns, and immigration. In an article on Time.com in November, for example, Mrs. Clinton was quoted as saying: “During the 1990s, I cannot remember being asked about immigration. Why? Because the economy was working. And average Americans didn’t have to go around looking for others to blame.”

Democratic strategists debated how much the comments would hurt Mr. Obama in the long term and whether they could swing the nomination to Mrs. Clinton. “Game-changer? No. Harmful? Yes,” a Democratic consultant who supports Mr. Obama, Daniel Gerstein, said.

Mr. Obama’s mistake was not just what he said, Mr. Gerstein argued, but where he said it — in San Francisco, a center of liberalism often derided by Republicans as culturally apart from the rest of America. “The first rule for Obama is: Stop going to San Francisco,” Mr. Gerstein said, suggesting that even though the senator was attending a fund-raiser, he should be focusing more on the general election and avoid the type of events that could link him to the left-wing of the Democratic Party.

Analysts said this latest flare-up is not as conducive to a formal speech — Mr. Obama’s forte — as was the controversy surrounding the anti-American comments of his former pastor, Rev. Jeremiah Wright. “The key for Obama is not to dig a deeper hole for himself,” a Democratic strategist who is interim dean of Boston University’s College of Communication, Tobe Berkovitz, said. A speech “would just reinforce that he’s on the defensive,” Mr. Berkovitz said.