Obama, Romney campaigns are walking fine line between negative and nasty ads

The 2012 race for the White House has been dominated by negative ads. With 99 days to go, the only question is how nasty it will become.

Both candidates have made no bones about the fact they’re going to attack one another, and each side already has been accused of making distorting statements and telling out-and-out lies. At the same time, President Obama and Mitt Romney have suggested there’s a limit to the mud they’ll throw. Yet in an election expected to come down to a handful of swing states, some think it will be harder and harder for the two sides to leave ammunition on the table as the race intensifies in the fall.