Former Maryland lieutenant governor Michael Steele didn't fare well as chairman of the Republican National Committee. (Getty Images)

As we prepare to head into the late summer political conventions, once again the Republican Party has no real African-American contender for the vice presidential slot, save for former Secretary of State Condoleezza Rice — and she has said pretty firmly that she is not interested in the job.

But what is critical for people to know is that there is a training ground for most successful presidential and vice presidential candidates, and it is usually in the governor and lieutenant governor’s mansion. Yes, U.S. senators have been tapped to run for president and vice president frequently; both current occupants of those jobs hail from the U.S. Senate. (Members of the House of Representatives, not so much.) But for African-Americans in the Republican Party — and there a few — there seems to be a “pox” on the house of the office of lieutenant governor, which is unfortunate, because that post is the stepping stone to becoming governor, and by extension, president.

Former Colorado lieutenant governors George L. Brown and Joe Rogers, former Maryland lieutenant governor Michael Steele, and current lieutenant governor of Florida Jennifer Carroll are the only black Republicans elected to serve in those posts in the history of the U.S.

Brown, Steele and Carroll were the first blacks of any political party to be elected statewide to such lofty positions. All three were dubbed a superstar upon their election with great hope for the future, yet each eventually flamed out politically.

The question is, why?

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In Rogers’ case, no-one really knows. He was a party darling, and then he was not. We haven’t heard much from him since President George W. Bush’s first term.

Michael Steele went on to become the GOP’s nominee for U.S. Senate in Maryland in 2006. He lost that race, but then became chairman of the National Republican Party in 2008, racked up historic congressional wins for Republicans in the 2010 midterm elections, and was ushered out the door as a “thank you” from his party.

As for lieutenant governor Jennifer Carroll, Republicans had high hopes for her. But the recent scandals surrounding an allegation of an affair with a female staffer, followed by insensitive comments by Carroll that women who “look like her” do not have lesbian liaisons (she later apologized) seems to be just more proof that the lieutenant governor’s job is a curse for the black Republicans who aspire to, and ultimately win, that position. There is no way, in my judgment, that Carroll recovers from this mess, even if the allegations are somehow proven “untrue.” It’s never the scandal that kills you in politics; it’s the lying, covering, and non-stop media coverage forever etched on the Internet that ultimately destroys people.

Clearly, the GOP has a problem attracting top black talent to the party. And when it does, as demonstrated by the examples above, they find a way to wreck themselves, or they get wrecked by the party they faithfully serve.

Sophia A. Nelson is a journalist, award winning author and entrepreneur. Her book, Black Woman Redefined, has been discussed in various media outlets. Follow Sophia A. Nelson on Twitter at @SophiaRedefined.