Obama Says Press Bites on Clinton Spin

From CBS News' Maria Gavrilovic:

HOUSTON -- Barack Obama described Hillary Clinton today as a "tenacious" candidate but blamed her for running a negative campaign. He said Clinton has employed a "kitchen sink" strategy in attacking him, and that negative ads running against him may have caused a sense of "turbulence" in the minds of voters.

"I am a little surprised that all the complaining about the refs has worked as it has for them. This whole spin of just how the press has been tough on them and not tough on us. I didn't expect that you guys would bite on that," Obama said.

Michelle Obama, who has been campaigning alone in Texas and Ohio, called her husband "calm, cool, and collected."

"You know this is a tough game, you know this is how it goes," Michelle Obama told the reporters on the plane. "This hasn't been anything other than what we expected. You have to be ready for tough questions and he's handled himself well."

Meantime, he continues to downplay expectations for today's contests, saying that the results will be very close and he doesn't expect Hillary Clinton to gain on his pledged delegate lead.

"We know there's not going to be a huge shift in delegates one way or another just given the math, which means that either way we will go to Mississippi and Wyoming next week." Obama told reporters on the flight from Houston to San Antonio.