ABOUT THOSE CROWDS…. In the midst of a massive push by the Obama campaign to undermine the McCain’s campaign’s credibility, we get yet another example that undermines the McCain’s campaign’s credibility.

Senator John McCain has drawn some of the biggest crowds of his presidential campaign since adding Alaska Governor Sarah Palin to his ticket on Aug. 29. Now officials say they can’t substantiate the figures McCain’s aides are claiming.

McCain aide Kimmie Lipscomb told reporters on Sept. 10 that an outdoor rally in Fairfax City, Virginia, drew 23,000 people, attributing the crowd estimate to a fire marshal.

Fairfax City Fire Marshal Andrew Wilson said his office did not supply that number to the campaign and could not confirm it. Wilson, in an interview, said the fire department does not monitor attendance at outdoor events.

At another recent appearance, the McCain campaign boasted of 10,000 people who attended an event in Pennsylvania. Asked how aides arrived at that number, the campaign said the Secret Service provided the figures. Soon after, the Secret Service said it had done no such thing.

In the grand scheme of things, are inflated crowd numbers the next big McCain/Palin scandal? Probably not. But it’s all about the context — this is a campaign that’s been lying relentlessly, about matters large and small, non-stop for weeks. Exaggerated crowd figures are minor, but when added to the ever-growing list, it points to a campaign that lies when the truth is nearly as good — in other words, a Republican ticket that lies even when it doesn’t have to.

The Obama campaign asked earlier today, after we learned that Sarah Palin had lied about having been to Iraq, “Americans are starting to wonder, is there anything the McCain campaign isn’t lying about?”

Expect to hear that phrase quite a bit.

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.