It has the ring of a bad-news story: the former governor of Massachusetts, Mitt Romney, acknowledging that, his earlier campaign boasts notwithstanding, he in fact never marched with Martin Luther King Jr. and that his father never did either. But the more you think about it, the more the flap is actually a sign of progress of America on matters of race.

Even after Clarence Thomas, Colin Powell, Condoleezza Rice, Rod Paige, and Alphonso Jackson, plenty of left-wingers still think of the Republican Party as a bastion of racism. One thing the Romney-King flap demonstrates is that they are wrong. If Mr. Romney really thought that the key to the Republican nomination was the racist Good-Old-Boy vote in South Carolina, Florida, and other states below the Mason-Dixon line, why would he be hyping his and his family’s own record on integration? If Republican voters were really as racist as a lot of left-wingers think they are, talk of Martin Luther King Jr. would likely repel voters rather than attract them.

So Mr. Romney can be faulted for his historical inaccuracy, but not for the meaning of his message. Democrats had a field day depicting Jesse Helms, Strom Thurmond, Trent Lott, Richard Nixon, and even Ronald Reagan as racists pursuing a “Southern Strategy” to win the White House. This isn’t the place to sort out the record of each of those men. Mr. Romney can perhaps be faulted for channeling the party’s bias against Hispanic immigrants. America today faces different civil rights struggles than it did in King’s era. But it’s hard for us to see Mr. Romney’s embrace of King’s legacy as anything other than a welcome, if clumsy, effort to restore the Republicans to their proper place as the Party of Lincoln.