The U.S. Chamber of Commerce is going on the air to rip Rep. Mike SimpsonMIchael (Mike) Keith SimpsonDuring a time of uncertainty, Great American Outdoors Act deserves our support Dentists want coronavirus testing kits before reopening MLB, Congress play hardball in fight over minor leagues MORE's (R-Idaho) Tea Party opponent for his work as a trial lawyer.


"Trial lawyer Bryan Smith stood in the way when conservatives tried to end junk lawsuits in Idaho. Smith opposed doctors, ranchers and small businesses, protecting his fellow trial lawyers instead. Trial lawyers like Bryan Smith are a part of the problem, wrong for Idaho," the ad's narrator says before touting Simpson as "conservative, Idaho strong."

This is the Chamber's first ad attacking Smith in the district. Their earlier ads had been positive spots touting Simpson's record.

Simpson, a close ally of House Speaker John Boehner (R-Ohio), is one of just a few Republican incumbents facing a real challenge from a Tea Party opponent. The Chamber's ad buy shows they are making it a top priority to keep him in office.

Smith's campaign fired back.

"This is just more proof that Idahoans are ready to send a real conservative to Washington in Bryan Smith. Mike Simpson's liberal record of supporting higher taxes, more spending, and even funding ACORN has finally caught up with him," said Smith Campaign Manager Carrie Brown.

Smith is the only House candidate challenging an incumbent who has the backing of the deep-pocketed Club for Growth, but Simpson has been the beneficiary of a renewed push by establishment Republican groups like the Chamber to fight back against the Tea Party. The race is a test of whether that effort will work.

This post was updated at 3:15 p.m.