From Sam Stein's piece on the event:
Republican pollster Bill McInturff was the keynote speaker on the final day of the America's Health Insurance Plans's state issues conference on Friday morning.
But his speech on how the health care reform debate was playing among the public was interrupted before it even began. A group of protesters began aggressively cheering McInturff for the work he has done for AHIP (he's a hired pollster for the private insurance lobby and, most infamously, was the force behind the 'Harry and Louise' ads in 1994)
McInturff, initially thinking that the cheering was legitimate, thanked the "AHIP officials" in the back of the room for giving him mental encouragement for his speech. He was not being paid for his appearance, he noted...
McInturff, who remarked earlier that he didn't have a joke to lead off with, pointed to the exiting protesters and said "there's my joke." But while his speech had been interrupted, the pollster actually admitted to being mildly impressed.
Stein also has the full lyrics. From the group's site, here's Rachel Maddow's coverage of the event:
This stunt gets major style points - all the more so because of the positive reactions from those not in on the gag. Most conferences get pretty dull, and this group performed very well. Watch out, corporate stooges! Guerilla theater is coming after ya!