Guess who isn't getting a primary challenge. Photographer: Andrew Burton/Getty Images
Guess who isn't getting a primary challenge. Photographer: Andrew Burton/Getty Images

(Corrects number of challengers faced by Graham and Scott in first and second paragraphs of article published May 8, and Scott's Heritage Action rating in fifth paragraph.)

Senate Republican leader Mitch McConnell of Kentucky has a Tea Party primary challenger. Speaker of the House John Boehner just dispatched one of his own this week in Ohio's Republican primary. Republican Senator Lindsey Graham, facing opposition from the right, has six candidates vying to unseat him in South Carolina's June primary.

You know who doesn't have a serious primary challenger, Tea Party or otherwise? Senator Tim Scott of South Carolina. That's intriguing. Appointed in 2013 by Governor Nikki Haley to fill the seat vacated by former Senator Jim DeMint, Scott is the first black Republican in the Senate since Edward Brooke of Massachusetts, who served in the era when Dino-RINOs of the Nelson Rockefeller and Charles Percy persuasion roamed the earth. (Randall Young of Greenville has filed papers to challenge Scott in the primary; according to the State newspaper, Young, who received 24 votes last time he ran for office, gave election officials only a post office box and a nonworking telephone number.)

Scott, a former House member with modest legislative accomplishments, has never run a statewide election. According to an April Winthrop University poll, 33.5 percent of registered voters in South Carolina say they don't even know enough about him to form an opinion. He has raised about $5 million, according to his most recent campaign finance report. On the same deadline, his in-state colleague Graham -- the guy who attracted four challengers -- reported having raised about $9 million.

The Washington Post this week profiled Scott as "the undercover senator" -- not exactly the strategic posture you'd expect from a little-known, unelected senator making his first statewide race in a party, and a moment, rife with anti-incumbent anger.

A South Carolina Republican told me that Scott's immunity from challenge stemmed from two sources: First, Scott placed himself so far to the right that there was no space for a Tea Party challenge on ideological grounds. He has an "F" on the NAACP legislative scorecard and a higher score on the right-wing Heritage Action scorecard -- 90 out of a possible 100 -- than fellow South Carolinian Joe "You Lie" Wilson.

Second, Scott benefits from a widespread recognition among Tea Partyers and conservatives in general that a high-profile black conservative is a thing most rare and precious. The act of supporting a black conservative is both an absolution for the past and a shield for the present and future. In South Carolina, where the Confederate battle flag still flies on the state capitol grounds, and where a recent lieutenant governor seemed a little too enthusiastic about all things confederate, that matters.

In effect, South Carolina Republicans treat Scott like the national party previously treated the ham-handed presidential candidate Herman Cain and the party's not-quite-competent chairman during Obama's first term, Michael Steele: They are members of an endangered political species for whom the bar is effectively lowered.

Affirmative action based on race has taken quite a beating at the Supreme Court, in state legislatures and at the ballot box. In the Republican Party, however, affirmative action can punch your ticket like nobody's business.

To contact the writer of this article: Francis Wilkinson at fwilkinson1@bloomberg.net.

To contact the editor responsible for this article: Tobin Harshaw at tharshaw@bloomberg.net.