I write as a guy who has worked in sales on and off over the years.
I perceive (I could be wrong here) that there is a meme on the left that is shooting us in the foot. It goes something like this:
"If we get the president to say something really stupid [the shortest wait in history] then, THEN John Q Public will finally wake up to his" (fraud, lies, hidden elitism, whatever). All we have to do is just be RIGHT enough, and everyone will see the light.
That's not the way it works.
You need a consistent message coming from everyone in the party, something like, "The president has consistently miscalculated on [insert issue here]."
"He miscalculated on Iraq, and just look at the mess he's made. He miscalculated on the Budget, and look at the mess he's made. He miscalculated on education, and just look at the mess he's made. He miscalculated on medicare, and look at the mess he's made..."
"Miscalculated...miscalculated...miscalculated...yet another miscalculation...to correct his miscalculation, the truth is that..."
Or maybe use "faulty"...but make it a deafening roar, make it consistent, flood the airwaves...
Reporter: "Senator Kerry, the president has said he's been better on [any, ANY issue]"
Kerry: "Well, given his record of miscalculation, I would ask in return..."
Reporter: "Senator Kennedy, you have criticized the president on [whatever]..."
Kennedy: "Well, given the president's record of miscalculation..."
Reporter: " Governor [Democrat], what is your position on [some budget question, say]..."
Governor: "Well, given that we have to deal with the financial miscalculations of our current president..."
Local Reporter somewhere: "Congressman Peabody, looks like the rain may soon stop."
Rep. Peabody (D, Anyoldplace): "Hey, given the way the president miscalculates, I wouldn't count on the sun 'til I see it in the sky..."
Choose a [winning] theme, and then let every utterance of our side reflect that theme, loudly and constantly.