Presidential Candidates Shift Strategies as Polls Tighten

Obama focuses on swing states, Mitt goes on the offense

With a little more than two weeks left until judgment day, Barack Obama's campaign is embracing a fundamentally defensive strategy centered on winning Ohio at all costs — while unleashing a new barrage of blistering attacks against Mitt Romney aimed at mobilizing a less-than-fired-up Democratic base.

A surging Romney is suddenly playing offense all over the map, and the upward movement since the Denver debate gives him the luxury of striking what his advisers — and more than a few Democrats — think is a more positive, presidential, "Morning in America" tone.