Out come the claws:

Hillary Rodham Clinton opened a five-day campaign to target what her aides call Barack Obama’s inexperience, delivering sharper attacks against the Iowa winner that are likely to become more personal and negative, according to Democrats familiar with the evolving strategy.

I think this may backfire on Hillary. All Obama has to do is to brush off these attacks as part of the same old politics he is trying to change. Also, Romney went negative in Iowa, and it seemed the more he did, the worse he did.

But Hillary doesn't have much choice here. If she doesn't attack, Obama wins. It will be interesting to watch just how much Hillary cares about her personal future over that of the Democrats.