SPRINGFIELD, Ohio— President Obama voyaged to Republican turf Friday, seeking to make inroads on less friendly terrain in the nation’s premier battleground by painting Mitt Romney as a gifted but untrustworthy salesman.

Obama told roughly 4,000 supporters here that he ushered in “real change” during his first term in office, highlighting the auto bailout, investments in the middle class and a new jobs report Friday that showed an uptick in hiring — and an increase in the unemployment rate.

“We’ll win Ohio,” Obama said to a crescendo of applause. “We’ll win this election.”

But more than anything, Obama sought to convince voters they couldn’t trust Romney, who remains in a dead heat with the president for Ohio’s 18 electoral votes.

The president ripped Romney for ads airing in Ohio that say Obama’s auto bailout forced General Motors and Chrysler to start building jeeps in China. The automakers counter that such claims are false.

“You don’t scare hard-working Americans just to scare up some votes,” Obama said at North Springfield High School, in a suburb of Dayton. “That’s not what being president is all about. That’s not leadership.”

The presidential contenders spent Friday trading jabs over who was the true agent of change and capable of working across the aisle.

“Candidate Obama promised change, but he couldn’t deliver it,” Romney said in Wisconsin Friday morning. “I promise change, but I have a record of achieving it.”

Both Obama and Romney are engaged in an all-out blitz across Ohio, so much so that the Buckeye State will host more presidential events than any other battleground between Friday and Election Day.

Obama on Friday looked to increase his exposure beyond just Democratic-leaning parts of the state. He lost this area, Clark County, to Sen. John McCain, R-Ariz., by 4 percentage points in 2008. Later Friday, Obama will travel to Lima, in a county he lost by 22 percentage points four years ago.

With Election Day just four days away, Obama also played cheerleader-in-chief.

“That’s surrender,” Obama said of Romney’s blueprint if elected. “And I’m not going along with it…I got a lot of fight left in me. I don’t get tired. I don’t grow weary.”