The Clinton campaign is touting a pair of Quinipiac polls showing her with commanding leads in Ohio and Pennsylvania of 21 points and 16 points, respectively. If she were to win those states by such margins, she could be in a position to catch Obama in the delegate race. But unfortunately for her, these contests are likely to tighten. For one thing, the polling period ended on Feb. 12, before news hit of Obama’s stunning trio of victories in the Potomac primaries. For another, Obama hasn’t campaigned in either state yet. There are almost three weeks between now and the Ohio primary, and more than two months before Pennsylvania. That gives him plenty of time to campaign there, spend money on ads, and ride his wave of momentum. So Clinton still may win there, but she’s unlikely to do so by wide enough margins to erode Obama’s delegate lead. It seems to me that these polls represent a ceiling of support for her, while for him they’re only the floor.