AFL-CIO chief Richard Trumka has asked insurance commissioners in Connecticut, New York, Indiana and Pennsylvania to investigate a possible connection between rate hikes by several large insurers and their Washington lobby expenditures.

In a letter Thursday, Trumka asked New York's acting insurance superintendent James Wrynn to look into the activities of Anthem Blue Cross and Blue Shield (now Wellpoint) and United Healthcare.

"We believe that health insurance providers' lobbying expenditures have led to excessive rate hikes and urge you to include a review of such expenditures," Trumka wrote.

Trumka makes several direct connections between insurance-rate jumps and lobby expenditures in the letter: "At the same time that Anthem Blue Cross and Blue Shield was preparing to request your approval to raise insurance premiums for Connecticut residents by up to 30 percent in some cases, [the company] spent more than $9.5 million on lobbying activities."

The carriers in question are currently examining the letter and we will update this story as soon as they respond to us. You can read Trumka's letter here:

(This story has been updated from an earlier version with the inclusion of more information on state recipients and an updated letter)