Reading between the lines in this new New York Times story, it looks like Romney’s birther joke was no accident.

Mitt Romney is heading into his nominating convention with his advisers convinced he needs a more combative footing against President Obama in order to appeal to white, working-class voters and to persuade them that he is the best answer to their economic frustrations.

And this …

But in a marked change, Mr. Romney has added a harder edge to a message that for most of this year was focused on his business and job-creation credentials, injecting volatile cultural themes into the race. [emphasis added]

In truth, this shouldn’t surprise us. The still terrible state of the economy simply hasn’t been enough to put Romney into the lead, not even with the decelerating job growth which began early in the year.

So it’s time for ‘volatile cultural themes’, euphemistic appeals to racial fears, ‘just havin’ fun’ cracks about Obama’s purported foreign birth, bogus claims about policy moves by a shiftless welfare-lovin’ Obama.

Get ready for a rollicking 10 weeks.