(CNN) -- Sen. Barack Obama's reference to "lipstick on a pig" has Republicans demanding an apology and Democrats accusing Sen. John McCain of a "pathetic attempt" to play the gender card. Barack Obama used the "lipstick" line at a campaign event in Lebanon, Virginia, on Tuesday. McCain's campaign said Obama's remarks were offensive and a slap at Republican vice presidential nominee Sarah Palin -- despite the fact that the Arizona senator himself used the phrase last year to describe a policy proposal of Hillary Clinton's. Obama shot back Wednesday and accused the McCain campaign of engaging in "lies" and "swift boat politics."
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NEW: Barack Obama slams Republicans for "lies" and "swift boat politics"
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Obama said Tuesday "You can put lipstick on a pig, but it's still a pig"
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McCain camp says line was an attack on Palin; Obama camp says it was not
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Many politicians have used the line; former McCain adviser used it in her book title
Virginia
Obama made his controversial "lipstick" remarks at a @placeholder campaign stop late Tuesday afternoon.
Sarah Palin
Palin
@placeholder used the line in the opening remarks of her convention speech, and she frequently uses it on the campaign trail.
John McCain
McCain
McCain
McCain
McCain
"This phony lecture on gender sensitivity is the height of cynicism and lays bare the increasingly dishonorable campaign @placeholder has chosen to run."