That's funny, I don't see every poster backing up the claim based on your understanding of the article. Cosmos, sure you're reading things right?
What part of the term, "state-wide elected office," do you not understand? I just went and read the article and it's talking about state-wide seats. It says right in the article that Congress, which is not a state-wide election, is different because the Democrats hold the edge. The artilce is about Governors and Senators primarily governors.
Nice leaving out the context to the numbers.
This is why it might surprise you to hear that Republicans are by far the more diverse party when it comes to statewide elected officials such as senators and governors. On this front, they leave Democrats in the dust. And that's why the GOP actually has a greater depth of diversity on their potential presidential bench looking to 2016 and beyond.