Midwest Airlines says an emergency evacuation slide on a charter to Barack Obama's campaign partially inflated during flight today. The slide that inflated was in the tailcone of the MD-80 charter. That led the pilots to make an unscheduled stop in St. Louis on the flight from Chicago to North Carolina.

Midwest says the issue was never a problem with the safety of the flight, but the pilots decided to make the unscheduled stop as a precautionary measure. Midwest says it has made alternative flight arrangements for Obama and his staff through a different charter service.

Midwest says the Obama campaign has been using Midwest's charter service on and off for the past several weeks.

On the ground in St. Louis, Obama read the paper in the front cabin, but ventured briefly to chat with the press at one point.

"I just thought we'd spice things up a little bit today," Obama said, smiling and joking.