TIME reported the McCain campaign released a Web ad that alleged Obama, at a campaign stop, referred to Palin as a “pig.”

It was the latest in a series of aggressive McCain ads that targeted Obama, as McClatchy reported:

McCain supporters said Obama was slyly alluding to Palin’s description of herself as a pit bull in lipstick, but there was nothing in his remarks to support the claim. Obama accused the GOP campaign of “lies and phony outrage.”

The next day, the AP reported Obama’s response:

Barack Obama on Wednesday accused Republican John McCain’s campaign of using “lies and phony outrage and Swift-boat politics” in claiming he used a sexist comment against vice presidential candidate Sarah Palin.

Calling it “the latest made-up controversy by the John McCain campaign,” Obama responded to the Republicans’ charge that he was referring to Palin when he used the phrase ”lipstick on a pig” at a campaign stop Tuesday.

The following week, McCain made an appearance on ABC’s The View, where:

Barbara Walters … pointed out that McCain too had used the lipstick phrase during the campaign.

McCain said he used the “lipstick” quote while talking about Sen. Hillary Clinton’s health care plan. Obama has argued he used the phrase while describing McCain’s claim that he would be a force for change if elected president.

Later, McCain admitted to the Associated Press that he didn’t believe Obama was calling Palin a pig.

Did Barack Obama really call Sarah Palin a pig, as a John McCain ad leads people to believe? “No,” McCain said Monday. The Republican presidential nominee defended the ad anyway, saying Obama “chooses his words very carefully.”

McCain also used the expression while campaigning in Iowa in October 2007. It was also used by Dick Cheney while campaigning during the 2004 election.

Here are clips of Obama, McCain and Cheney using it: