Yesterday, we talk about how the Democratic presidential race was poised to enter a new phase -- with the race for the nomination down to the top two, Hillary Clinton and Barack Obama will start making the case that they can beat Republicans in general, and John McCain in specific, in a general election.

I consider this a very positive development. Entering this phase of the contest will help Obama and Clinton focus their message in a helpful way -- highlighting what's wrong with the McCain/GOP agenda, and how best to beat it in November.

We got our first real taste of this new phase early on last night.

Q: Senator Obama, one other thing both of your health insurance proposals have in common is they would cost billions of dollars in new spending, and both of you have proposed raising taxes on a lot of Americans to pay for that and for other proposals. Well, now, you know what's going to happen this fall in the general election campaign: The Republicans are going to call you tax-and-spend liberal Democrats, and that's a charge that's been effective in the past. How are you going to counter that charge?

OBAMA: Well, first of all, I don't think the Republicans are going to be in a real strong position to argue fiscal responsibility when they've added 4 (trillion dollars) or $5 trillion worth of national debt. (Cheers, applause.) You know, I am happy to have that argument.

If John McCain, for example, is the nominee, I respect that John McCain in the first two rounds of Bush tax cuts said it is irresponsible; that we have never before cut taxes at the same time as we are going into war. And somewhere along the line the Straight Talk Express lost some wheels -- (laughter) -- and now he is in favor of extending Bush tax cuts that went to some of the wealthiest Americans, who don't need them and were not even asking for them.