President Barack Obama heads to Elkhart, Indiana, on Wednesday to tout the economic progress made since his first visit there in 2009, but he is also expected to wade into the 2016 election -- and he's "ready to go" on the campaign trail, a source says.

Obama is chomping at the bit to get out and "get people fired up," a White House source said, but the President will remain largely on the sidelines until the Democrats have a nominee.

Obama expects to "explode onto the scene" once the nominee is selected and "knows his power" to fire up the Democratic base, the source said.

"It's driving him crazy" to be mostly hands off at this time, the source added