Former senator Larry Pressler (R-S.D.) is apparently set to throw a wrench into the open South Dakota Senate race.

The Rapid City Journal reports that Pressler, who is looking at running as an independent, has scheduled a multi-city announcement tour for Dec. 30.

From the Journal:

"I'm moving in the direction of announcing," Pressler, 71, said in phone interview Thursday from his home in Sioux Falls.

While Pressler won't say for certain that he is going to jump into a race that already features five Republicans and one Democrat, he has scheduled a press conference for 2 p.m. on Dec. 30 at the Hotel Alex Johnson in Rapid City. Press conferences are also scheduled in Sioux Falls, Aberdeen and Watertown.

Multi-city announcement tours aren't generally planned by candidates who aren't going to run.

The presence of Pressler, a former three-term senator, in the race might cause Republicans some heartburn. Right now, former governor Mike Rounds (R) is a heavy favorite to succeed Sen. Tim Johnson (D-S.D.), who is retiring, but three-way campaigns are notoriously unpredictable.

Democrat Rick Weiland is running but doesn't have the unified support of his party at this point.