Check your calendar on this March 31st.  The Pennsylvania primary still has three weeks left for campaigning.  Then it is a break of two weeks after that until Indiana and North Carolina on May 6.

Both Hillary Clinton and Barack Obama are advertising in Pennsylvania already.

But only Obama is now up with ads in Indiana and North Carolina.

As we have seen throughout this Democratic race, Obama has been able to devote millions more to advertising in just about every battleground.  Super Tuesday showcased his advantage the best, when he was on the air in ten states - and Clinton had no ads there at all.

With the conventional wisdom that Clinton will win in Pennsylvania, Team Obama has obviously decided that there is no reason to wait too long to go up with ads in the May 6 states.

I really believe that a double win that day for Obama in Indiana and North Carolina would pretty much end this race.  The betting will be that Obama wins in the Tar Heel State while Clinton wins in Hoosier-land.

Obama's ad in Indiana is clearly aimed at working class whites, emphasizing economic issues like trade and job losses.

So far, Hillary Clinton is not on TV in either state.  When asked about that by the Louisville (KY) Courier-Journal, Clinton said, "We'll get around to it. He's going to outspend me everywhere. He'll outspend me on TV. But I think it's important for me to introduce myself and for people to get a more personal feel for me."

Meanwhile, an introductory ad by John McCain sparked finger-pointing over the weekend, after Democratic National Committee chairman Howard Dean blasted McCain.

The ad, which features footage of McCain as a POW in Vietnam, was ripped by Dean:

"While we honor McCain's military service, the fact is Americans want a real leader who offers real solutions, not a blatant opportunist who doesn't understand the economy."

The words "blatant opportunist" naturally drew the ire of the Republican National Committee Chair Mike Duncan.

"I call on both Senators Obama and Clinton to denounce Howard Dean for stating that Senator McCain is a "blatant opportunist" for discussing his record of military service with the American people," said Duncan.

Look for this argument to be repeated a lot between now and November....