Republicans might be so scared of Rush Limbaugh that they don't care about public opinion and refuse to take him on, but private companies are a different matter.
The national mattress chain Sleep Train was the first to bail.

We don't condone negative comments directed toward any group. In response, we are currently pulling our ads from Rush
with Rush Limbaugh.
— @theSleepTrain via Twuffer
They've been joined by Select Comfort/Sleep Number.

Recent comments by Rush Limbaugh do not align w/our values, so we made decision to immediately suspend all advertising on that program.
— @SleepNumberSara via web
And Quicken Loans.

Due to continued inflammatory comments– along w/valuable feedback from clients & team members– QL has suspended ads on Rush Limbaugh program
— @quickenloans via web
And the Cleveland Cavaliers, at least temporarily:
The Cleveland Cavaliers have decided to suspend any and all on-air advertising with the Rush Limbaugh radio program, citing “inflammatory comments” coupled with valuable feedback from both clients and team employees.
Then there's
ProFlowers, which seems pretty darned committed to not taking a strong stand on this one. Here's a representative tweet to a disgruntled customer.

@utbrp We would like to assure you that we do not endorse the views expressed by Rush Limbaugh and we appreciate your feedback.
— @ProFlowers via web
Seriously, a flower company? Is there really a market for sending your girlfriend flowers from someplace known for siding with the guy who calls people 'sluts'? That there is a questionable marketing decision.
Other companies are working hard to distance themselves from Limbaugh:
The Twitter feed of online dating site eHarmony read, "We’ve never paid for ads on Limbaugh show. We’re looking into the matter of 'network buys' and will let you know what we discover." (Updated at 4:25 p.m. ET.: Spokeswoman Becky Teraoka said via e-mail, "We do have that confirmation" that a network buy did not land eHarmony advertising on Limbaugh's show.)
Ray Pohlman, spokesman for AutoZone, said the company had never advertised with Limbaugh and was working with its media buyers to find out if any ads did air. "If a commercial ran, it was in error," he said. "We're running it down."
Keep up the pressure.
Sign the petition telling advertisers to dump Rush.
6:25 PM PT (Barbara Morrill): Another company pulls their advertising!

We have listened to our customers & have decided to cease our advertising on The Rush Limbaugh Show immediately.
https://t.co/...
— @citrix via web
7:01 PM PT (Barbara Morrill): One more ... keep up the pressure!

@drpfox As of today, LegalZoom has suspended all advertising on the Rush Limbaugh show.
— @LegalZoom via HootSuite