WASHINGTON (AFP) - Democrats Thursday accused a "desperate" John McCain of offering voters a paucity of hope, after the Republican invoked Britney Spears to damn Barack Obama as nothing more than a glitzy showman. Obama's White House campaign, berating McCain for stooping to the "low road" of politics, pounced on newspaper headlines across the United States that castigated the Republican contender's new negative tone. But McCain aides, basking in the huge media buzz generated by an attack ad likening Obama to pop diva Spears and celebrity socialite Paris Hilton, defended the Arizona senator from charges that he has nothing positive to say. "You know, the last time I saw Britney Spears on stage with a politician, the guy looked a lot like John McCain. Because that's who it was. It was John McCain," Obama's communications director Robert Gibbs observed on MSNBC. Gibbs appeared to be referring to McCain's attendance at the 1999 MTV music awards in New York, when Spears performed. The singer has since spoken of her respect for President George W Bush. "The McCain campaign has decided, apparently, that the best way and the only way that they can win this campaign is to become very personal and very negative," he told MSNBC. "Look, we're going to let them take the low road. It's a place that they feel very comfortable in. We're going to talk about the issues that are facing this country, joblessness in this county and how to create good jobs." The Obama campaign responded to McCain's "Celeb" ad with its own called "Low Road", which accused the Republican of practising "the politics of the past." The Democratic Party also punched back with an ad entitled "Desperate Times." "Like so many other promises cast aside in his pursuit of the White House, John McCain's promise to run a respectful campaign didn't even make to his convention," Democratic National Committee spokeswoman Karen Finney said. "We all respect John McCain's service to our country, but he has clearly become an honourable man running a deeply dishonourable campaign. The American people deserve better, and John McCain knows it," she said. However, polls suggested that McCain's attempts to portray Obama as a liberal elitist who is only at home in the adulation of adoring crowds are making some inroads. McCain is gaining on the Illinois senator in the pivotal swing states of Florida, Ohio and Pennsylvania, according to new Quinnipiac University polls. The Connecticut university said Obama had seemingly gained no traction from a much-hyped foreign tour last week that was designed to flag his credentials to serve as commander-in-chief. In Florida, according to the survey, Obama has 46pc to McCain's 44pc, compared to a 47-43 edge for the Democrat in mid-June. The numbers were the same in Ohio, 46-44pc for Obama, from a 48-42 lead last time. In Pennsylvania, Obama has a slightly bigger lead of 49-42pc, compared to 52-40pc last month. According to a CNN/Opinion Research poll late Wednesday, 40pc of respondents believe McCain is attacking Obama unfairly, nearly double the number who find Obama's attacks on McCain unfair. But the poll also said 37pc found Obama arrogant, and 44pct felt the Democrat was acting as if he has already won November's election.