With the race extremely tight and little time left for a breakout moment, Obama is intent on getting the porridge just right in a 90-minute, one-on-one faceoff Tuesday at Hofstra University on New York's Long Island.

The candidates will take questions on domestic and foreign policy from an audience of about 80 of the coveted uncommitted voters whom both campaigns are so furiously courting with just three weeks left until Election Day. The town hall-style format makes it especially tricky for Obama to strike the right balance in coming on strong against Romney without turning off the audience — and tens of millions of television viewers — by going too negative.

The importance attached to this year's debates is reflected in the significant chunks of time that both candidates have spent preparing. Obama, faulted for being ill-prepared for the first faceoff with Romney, largely dropped out of sight for the last three days to attend "debate camp" at a resort in Williamsburg, Va. And Romney, the clear victor in Round One, has devoted big blocks of time to rehearsals over the last several days as well.