President Obama kicked off the fall campaign season Monday by pushing for a higher minimum wage and several other top Democratic priorities during a visit to Wisconsin.

Speaking at a Laborfest event in Milwaukee, Obama made the case for a federal minimum wage increase, noting that 13 states and Washington, D.C., have already raised their state minimum wages.

“There’s no denying a simple truth: America deserves a raise,” he said.

The choice of Wisconsin for a Labor Day event was deliberate. A deeply polarized state, it has been the epicenter of a major fight in recent years over the power of government workers' unions with a highly competitive governor's race this fall.

Clad in a blue button-down shirt with the sleeves rolled up, his more casual campaign-style garb, Obama touted the role unions play in protecting teachers, firefighters and service industry workers.

“If I were looking for a job with some security for a family, I would join a union,” he said. “I’d want a union looking out for me … and I’d want more Democrats in Congress looking out for me — I’m just saying.”

Obama also repeatedly cast Republicans as unreasonable obstructionists who are dead set against working with him on everything from immigration to equal pay for women to raising the minimum wage.

“These are just a few things that will help working families get ahead,” he said. “And Republicans are opposed to almost all of them.

“I’m just telling the truth. The sky is blue today. Milwaukee brats are delicious. The Brewers are tied for first place. And Republicans in Congress love to say no. ... They say no to everything."

Obama’s visit to Wisconsin came as polls show Republican Gov. Scott Walker slightly trailing his Democratic challenger, Democrat Mary Burke.

With Obama’s poll numbers near historic lows, Democratic candidates in tough races around the country have avoided making appearances with him when he travels to their state or district.

The president’s approval rating is slightly better in Wisconsin, where voters are even more divided about their governor than they are about their president.

Still, Burke was no exception Monday. She didn’t share the stage with Obama and chose to meet with him only privately.

The Republican National Committee said Obama’s trip to Wisconsin to stoke union support for Burke and other Democrats this fall shows that Democrats are facing an uphill battle this election.

The RNC cited divisions among unions when it comes to Obamacare, the administration’s environmental regulations and his indecision on the Keystone XL oil pipeline, which would extend the pipeline from Canada to the Gulf Coast of Texas and which unions support because of the jobs it’s expected to create.

“The Democrat base is not enthusiastic to vote, and labor unions and labor voters have become increasingly frustrated with President Obama,” said RNC spokeswoman Kirsten Kukowski. “President Obama’s problems with unions should cause Democrats everywhere to worry.”