Rush Limbaugh, the Republican Party and Women

It's been more than a week since Rush Limbaugh called a Georgetown law student a "slut" and a "prostitute" during his radio show, after Sandra Fluke testified on Capitol Hill about the need for health insurers to provide birth control to liberate women for the work force and protect against disease. Limbaugh insists that reports of advertiser defections have been exaggerated, but liberal groups say he's taking a lot of hits. President Obama has been asked about him, and Republicans are on the defensive about their popularity with women. The top three presidential candidates have said very little, and some conservative writers have said Republicans are "afraid" of arousing Limbaugh's animosity. With an audience of 15 million devoted listeners, how much do his views and opinions reflect those of the GOP as a whole?