President Obama is committed to making sure middle class families do not see a tax increase, White House Press Secretary Robert Gibbs said Monday, after two top economic officials seemed to leave the door open to such a tax hike. "The president's clear commitment is not to raise taxes on those making less than $250,000 a year," Gibbs said, repeating Obama's pledge from the presidential campaign. That was after Treasury Secretary Tim Geithner suggested Sunday that taxes increases are inevitable. "We will not get this economy back on track, recovery will be not strong and sustained, unless we ... can...