My, how times have changed.

Hillary, whose candidacy rationale was once that she should be the nominee simply because it was inevitable is now clinging to the promise of internal polling in Pennsylvania and the whims of shaky superdelegates for a longshot at delivering the prize she had counted on in the halcyon days of early 2007.

Once she was evitable, so to speak, she had no back-up, no secondary rationale. In the months since inevitability fell apart, Hillary has flailed for a new central message. She's been "tested," "vetted," "ready from Day One," and who could forget that she's a "fighter" who's been up against the "noise machine" during her "35 years of public service?"

For Obama, the rationale has been that he is a uniter, a new kind of politician, a post-racial advanced breed of public servant fit only for uplift and unfit for mudfights. But, as the Jeremiah Wright dust-up and his small-town voter remarks have begun to reveal an arrogance behind his honor, to hint at a shyster behind the smile, does Obama have a secondary rationale to offer?

Now that the race has become a mudfight, and he may have to get his hands dirty to win, hasn't he gotten himself into a situation where standard campaign-trail toughness undercuts the very rationale for his candidacy? Slamming Hillary on every stop of a whistle-stop campaign isn't new politics.

Despite his protestations that he's not running "to play the game better, but to stop the game-playing," it's standard fare, very, very old politics, and the voters of Pennsylvania and media alike are noticing.

On a train tour of Pennsylvania this week, Obama took a tougher tone with Hillary, and not everyone appreciated it: http://www.observer.com/2008/obama-gets-nasty

One woman in the crowd, Lisa Barsky, 55, a psychologist from nearby Bala Cynwyd described herself as a "shifter" who had moved her support from Clinton to Obama because she considered him a greater unifying force. Still, she was a little put off by his attacks.

"I wish he wouldn't," she said. "He can be strong. But you don't have to get down to somebody's level -- you don't have to get into the fistfight."...

"A couple of times I said to myself, 'That's not true,'" Jill Carney, 51, an undecided Democrat and college teacher from Lancaster, said of Obama's comments about Clinton and her policies. Asked what effect his more pointed comments had, she responded, "It makes me go the other way."