On a day dominated by news of Boeing’s major expansion in North Charleston, both sides in the 1st Congressional District race swapped accusations over their supposed ties to organized labor.

Labor unions have been a favorite political whipping boy for South Carolina Republicans even before the National Labor Relations Board challenged Boeing’s initial decision to build in the Lowcountry. The board withdrew its case in December 2011.

Democrat Elizabeth Colbert Busch released a new TV ad Tuesday vowing not to “take any special interest pledges or follow any party line.”

But Republican Mark Sanford’s campaign spokesman Joel Sawyer and the National Republican Congressional Committee issued statements criticizing Colbert Busch for claiming to be independent while accepting almost $30,000 in donations from unions.

Then the S.C. Democratic Party issued a statement calling Sanford a “colossal hypocrite” because he took at least $9,000 from organized labor in 1998, when he was in Congress.

That in turn prompted Sawyer to issue a statement calling the party “wrong and reckless” because those donations actually went to Sanford Bishop for Congress from Georgia.

“This is yet another example of Democrats playing fast and loose with the facts in an effort to distract from their candidate being beholden to the union that tried to shutter Boeing,” he said.

Reach Robert Behre at 937-5771.