Third-party groups on both sides of the political aisle are spending big on advertising this fall - but not at the same rate. Judy Woodruff talks with Evan Tracey, founder of the Campaign Media Analysis Group, for details.

As lawmakers and the president wrangle over the details of health care reform, interest groups across the political spectrum are taking to the airwaves in response to the numerous proposals coming out of Washington. Media expert Evan Tracey speaks with…