Hillary Clinton might have won Pennsylvania's Democratic primary, but -- no surprise, coming from him -- in his speech Tuesday night Barack Obama went a long way toward changing the subject, and no doubt scored some points along the way.

Obama's nod toward Clinton's victory was gracious, but it didn't last long:

I want to start by congratulating Senator Clinton on her victory tonight, and I want to thank the hundreds of thousands of Pennsylvanians who stood with our campaign today.

There were a lot of folks who didn't think we could make this a race when it started. They thought we were going to be blown out. But we worked hard, and we traveled across the state to big cities and small towns, to factories and VFW halls. And now, six weeks later, we closed the gap. We rallied people of every age and race and background to the cause. And whether they were inspired for the first time or for the first time in a long time, we registered a record number of voters, and it is those new voters who will lead our party to victory in November.

From there, he transitioned seamlessly into the substance of his address, getting on message about the "the fierce urgency of this moment" and -- perhaps in a nod to the most recent debate between the two Democrats, and the uproar over it -- adding, "It's easy to get caught up in the distractions and the silliness and the tit-for-tat that consumes our politics; the bickering that none of us are immune to, and that trivializes the profound issues -- two wars, an economy in recession, a planet in peril."

That was a theme that ran throughout his speech, as he dismissed politics as usual and called for solutions to the problems Americans face. In doing so, he managed another neat trick, positioning himself mainly in opposition not to Clinton but to President Bush and to John McCain. It's not a unique tactic, and the message it seemed intended to send -- that he's already past Clinton and is focusing on the general election -- isn't new, but the way Obama did it Tuesday was deft:

We're not here to talk about change for change's sake, but because our families, our communities, and our country desperately need it. We're here because we can’t afford to keep doing what we've been doing for another four years. We can't afford to play the same Washington games with the same Washington players and expect a different result. Not this time. Not now.

We already know what we're getting from the other party's nominee. John McCain has offered this country a lifetime of service, and we respect that, but what he's not offering is any meaningful change from the policies of George W. Bush...

We already know that John McCain offers more of the same. The question is not whether the other party will bring about change in Washington -- the question is, will we? ...

In every election, politicians come to your cities and your towns, and they tell you what you want to hear, and they make big promises, and they lay out all these plans and policies. But then they go back to Washington when the campaign's over. Lobbyists spend millions of dollars to get their way. The status quo sets in. And instead of fighting for health care or jobs, Washington ends up fighting over the latest distraction of the week. It happens year after year after year.

Well this is your chance to say, "Not this year." This is your chance to say, "Not this time." We have a choice in this election.