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Barack Obama today accused the McCain campaign of underhanded tactics in portraying his "lipstick on a pig" remarks about the Republican ticket as a misogynistic attack on vice-presidential nominee Sarah Palin.

The Democratic nominee came out fighting after his Republican rivals expressed outrage at his remarks.

“I don’t care what they say about me. But I love this country too much to let them take over another election with lies and phony outrage and Swift-boat politics,” he said, on a visit to a school in Norfolk, Virginia. "Enough is enough.”

His remarks referred to the Swift Boat Veterans for Truth, a group that in 2004 severely damaged the campaign of Democratic nominee John Kerry with unsubstantiated allegations about his decorated military record in Vietnam. The phrase has since become synonymous with political smear tactics.

Mr Obama has adopted a more aggressive stance in recent days as white female voters defect to the Republicans following the selection of Mrs Palin, the first female governor of Alaska. Yesterday, he appeared to be attempting to counter his rivals’ claim to the mantle of change when he said of Republican policy: “You can put lipstick on a pig, but it’s still a pig.”

The McCain campaign claimed the analogy was a sexist attack on Mrs Palin, who at last week’s Republican convention likened herself, as a “hockey mom”, to a pitbull in lipstick. It quickly released a web ad, “Lipstick”, directly linking Mr Obama’s remarks to the mother-of-five, and demanded that the nominee apologise for his “offensive and disgraceful” comments.

But, on the stump today, Mr Obama said the row was a diversionary tactic by the McCain campaign to avoid discussion of weightier issues.

“What their campaign has done this morning is the same game that has made people sick and tired of politics in this country. They seize on an innocent remark, try to take it out of context, throw up an outrageous ad because they know that it’s cat nip for the news media,” he said.

“The McCain campaign would much rather have the story about phony and foolish diversions than about the future,” the Illinois senator added.

“Every four years this is what we do. We’ve got an energy crisis. We have an education system that is not working for too many of our children and making us less competitive. We have an economy that is creating hardship for families all across America. We’ve got two wars going on. Veterans coming home not being cared for. And this is what they want to talk about."

The Obama campaign pointed out that Mr McCain himself had used the “pig in lipstick” analogy only last year to describe Hillary Clinton’s healthcare plan. It denied the nominee had been referring to Mrs Palin, noting that he used the analogy in the context of discussing Mr McCain’s policies.

“John McCain says he’s about change too,” Mr Obama had said. “I guess his whole angle is, watch out George Bush, except for economic policy, healthcare policy, tax policy, education policy, foreign policy and Karl Rove-style politics, we’re going to really shake things up in Washington.

“But that’s not change, that’s just calling the same thing something different. You can put lipstick on a pig, it’s still a pig. You can wrap an old fish in a piece of paper called change. It’s still going to stink after eight years.”

McCain campaign spokesman Brian Rogers responded to the nominee’s comments in Virginia today, saying: “Barack Obama can’t campaign with schoolyard insults and then try to claim outrage at the tone of the campaign. His talk of new politics is as empty as his campaign trail promises.”

Mr Obama is trying to claw back his lead from Mr McCain after polls showed the Republican nominee with an edge of up to five points following his selection of Mrs Palin.

The little-known governor was chosen in part to attract former Hillary Clinton supporters angry at perceived sexism during the primary race and, so far, the strategy appears to be working.

An ABC News-Washington Post survey found that, after Mrs Palin’s nomination, white women have moved from backing Mr Obama by 8 points to supporting McCain by 12 points.

Overall, the poll showed Mr Obama still ahead of Mr McCain by a statistically insignificant one percentage point, 47 to 46. But the daily Gallup Poll tracking survey showed Mr McCain jumping to a 5-point margin, 49 to 44.

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