A prominent member of the Republican National Committee is calling for the national organization to investigate the “racially divisive ads and robocalls” that targeted conservative state Sen. Chris McDaniel in Mississippi’s Republican Senate run-off last month.

Ed Martin, the chairman of the Missouri Republican Party, sent a letter to RNC chairman Reince Priebus requesting him to appoint a special committee of RNC members to “investigate this matter” and report back on its findings. The Daily Caller was provided a copy of that letter.

Martin wrote that an investigation is needed because “many of us are unsure of all of the facts and seek more.”

“Specifically, if one of our own members helped finance ads or robocalls that tarred tea partiers as a group as racists, I am sure that most RNC members would find that deeply offensive, indeed unacceptable,” Martin wrote.

“We cannot object to the left smearing conservatives with such labels if we do not rebuke those on our side who sink to such tactics.”

Incumbent Mississippi Sen. Thad Cochran squeaked out a win over McDaniel in the GOP Senate run-off. Many of McDaniel’s conservative supporters are furious that Cochran appeared to have won because his campaign convinced Democrats to cross party lines to vote.

There have been allegations that Cochran supporters played the race card to encourage African-Americans, many of whom usually vote in Democratic primaries, to vote against McDaniel.

One reported anti-McDaniel robocall went: “The time has come to take a stand and say NO to the tea party. NO to their obstruction. NO to their disrespectful treatment of the first African-American president.”

Another reported anti-McDaniel flier claimed that the “tea party intends to prevent blacks from voting” and accused McDaniel of racist comments and a voting history at odds with black voters.

In a separate email to RNC members, Martin wrote of his desire for an investigation: “I do not mean for this to be hostile but I do mean this to be about truth-telling.”

“My purpose in this is for us — we the RNC — to lead and help find out exactly what happened and move past it,” Martin wrote. “I consider this type of leadership central to our role as party leaders.”

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