DELRAY, Fla. — President Barack Obama says the most serious issue in the White House race is who voters can trust.

Obama is aiming to draw a contrast with Republican rival Mitt Romney following their final presidential debate. The president says that while Romney is shifting his positions on key issues, voters 'can trust that I say what I mean."

The president is also putting fresh emphasis on his second-term agenda, following criticism that he hasn't provided enough specifics about what he would do with four more years in office.

At a rally Tuesday in Florida, Obama ticked through a series of previously introduced policy proposals, including boosting education spending and manufacturing.