If Barack Obama had attended a 58th birthday party thrown in his honor Sunday on the South Side, he would have encountered thousands of paintings of Barack Obama staring back at him.

The exhibit, featuring an Obama painting for every day the former president was in office, graces the halls of the Stony Island Arts Bank, an old bank at 6760 S. Stony Island Ave. that was turned into a community center and gallery space.

It seemed a fitting spot for an Obama birthday party.

Rob Pruitt, the New York artist behind the work, admitted that an oversight may have accounted for the lack of a formal invitation to Obama.

“But the Obama Foundation has a table here,” he said in his defense, pointing to two foundation staffers who were eager to chat about their efforts to tap the public for help in their quest to collect Obama “artifacts” for the presidential museum that will soon take shape down the road in Jackson Park.

It wasn’t immediately clear how the former president spent his birthday. A foundation spokeswoman didn’t return a message seeking comment.

As a DJ played a set Sunday afternoon in a outdoor space adjacent to the old bank, attendees signed a giant birthday card for Obama.

Live music and birthday cake were also part of the festivities.

The party was open to the public and free. Many Obama fans attended.

“I think it’s awesome. I can’t wait to go get my mom and bring her here; she’d appreciate this,” said Lisa Gilbert, a forensic scientist with the Illinois State Police, as she marveled at the artwork. “She’ll be 88 in a few days and I know that she never thought she’d live to see an African American president.”

The art exhibit ends Aug. 25.

Pruitt isn’t sure where it will end up — perhaps in storage back in New York. But, for him, it’s meaning is unequivocal.

“In today’s America, with this current administration, any window we can open to let some fresh air in is OK,” Pruitt said. “It’s OK to be nostalgic, especially when it involves those ideals that are important to us.”

Pruitt volunteered for the Obama’s campaign.

“I didn’t want to close down my enthusiasm,” said Pruitt.

As he walked the gallery, a security guard told him: “You can’t have that drink in here.”

He smiled and set his styrofoam cup down without mentioning who he was.