A number of prominent conservatives have begun to rebuke charges by Rush Limbaugh, Newt Gingrich and others that Sonia Sotomayor is a 'racist.'

Sen. John CornynJohn CornynRepublicans divided over legislation protecting Mueller Democrats mull audacious play to block Pompeo Overnight Energy: Senate confirms Bridenstine as NASA chief | Watchdog probes Pruitt’s use of security detail | Emails shine light on EPA science policy changes MORE (R-Tex.), a member of the Judiciary Committee, called the charges "terrible."

"This is not the kind of tone any of us want to set when it comes to performing our constitutional responsibilities of advise and consent," Cornyn told NPR.

As chairman of the National Republican Senatorial Committee (NRSC), Cornyn is charged with helping Republicans chip away at Democrats majority, a task that will be much more difficult if Republicans alienate Hispanic voters with heated rhetoric.

"Neither one of these men are elected Republican officials," Cornyn said of Limbaugh and Gingrich. "I just don't think it's appropriate. I certainly don't endorse it. I think it's wrong."

A handful of conservative columnists have urged Republicans to tone down the rhetoric as well.

In her Wall Street Journal column today, Peggy Noonan scolded the firebrands, telling them to "play grown up."

"Newt Gingrich twitters that Judge Sotomayor is a racist," Noonan wrote. "Does anyone believe that? He should rest his dancing thumbs, stop trying to position himself as the choice and voice of the base in 2012, and think."

Likewise, Charles Krauthammer insisted conservatives stop the "ad hominen attacks."

"Use the upcoming hearings not to deny her the seat, but to illuminate her views," he wrote in a column today. "No magazine gossip from anonymous court clerks. No 'temperament' insinuations. Nothing ad hominem. The argument should be elevated, respectful and entirely about judicial philosophy."

At this point, Senate Republicans have got to be nervous that they're losing control of their message...