Vice President Biden. (Jay LaPrete -- Associated Press)

Updated, 2:01 p.m.

Vice President Biden will head to South Carolina in the days before the special election featuring Stephen Colbert's sister, timing her campaign calls "coincidental."

Biden will speak at the state Democratic Party's Jefferson-Jackson Dinner on May 3 -- an event that benefits the state party but not Colbert Busch directly. Colbert Busch is set to attend the party's convention on Saturday, though not necessarily the dinner on Friday, according to a South Carolina Democratic operative who spoke on the condition of anonymity because the plans were not solidified.

"The timing of the vice president's visit to South Carolina is purely coincidental," said Colbert Busch spokesoman Catherine Christman. "The South Carolina Dem Party invited VP Biden to address its annual dinner. The vice president will not be coming to the 1st District while he is in the Palmetto State, and Elizabeth will be totally involved campaigning in the 1st District while he is in town."

Biden's visit could also be seen through the prism of his 2016 presidential ambitions. South Carolina remains one of the earliest primary states, which means it can expect a strong dose of hopefuls like Biden in the coming years.

The event will take place in Columbia, which is in a different part of the state than the district that Colbert Busch is running in. The special election is set for May 7.

Biden and the White House may be taking a wait-and-see approach to supporting Colbert Busch's campaign. Any time the White House gets involved in a special election, it threatens to become something of a referendum on the president. And the White House may want to avoid taking the side of a losing candidate.

It remains to be seen whether Colbert Busch will be competitive in a district that gave Mitt Romney 58 percent of the vote in the 2012 presidential race. Democrats think she has a much better chance if scandal-tarred former governor Mark Sanford emerges victorious from next week's GOP primary runoff against former Charleston county councilman Curtis Bostic.

-- Sean Sullivan contributed to this post