It was still the talk of the cable TV networks and on talk radio, but the story didn't move much before the Pope arrived, as he took charge of the news.

Whether that changes tonight will depend on how the "bitter" issue is broached during the Democratic debate in Philadelphia and whether it produces any memorable sound bites or exchanges.

Obama didn't ignore it on Tuesday, as his campaign put out a new ad to respond to one released a day earlier by the Clinton camp, which had Pennsylvania voters expressing unease about Obama's comments.

Here is the ad, with copy provided by the Obama campaign.  It begins with a sound bite from Hillary Clinton:

Clinton:  I know that many of you, like me...were disappointed by recent remarks that he made (jeers)

Announcer:  There's a reason people are rejecting Hillary Clinton's attacks.  Because the same old Washington politics won't lower the price of gas or help our struggling economy.  Barack Obama will represent all Americans.  He offers a new approach.

Obama: When we get past the politics of division and distraction and we start actually focusing on what we have in common, there's nothing we can't accomplish...

It's a riff that I have heard from Obama a number of times this year and it has great appeal.  Obama offers something "new," no "politics as usual," a way to end gridlock in Congress, etc.

It always gets applause on the stump, though many have expressed skepticism that Obama can actually produce that kind of "new" politics.

What was most interesting to me was the use of the sound bite of Clinton where she was jeered in Pennsylvania the other day as she brought up the "bitter" issue.

It's so classic for Clinton at this point that I shake my head in amazement.  Obama hands her this issue, but she pushes it so hard, maybe too hard, that it boomerangs on her and ends up in Obama's ad responding to her attacks.

Is the "bitter" battle over?

That depends on what happens in Philly tonight.