In the air wars of the 2012 presidential campaign, this industrial town of 45,000 could stake a claim as ground zero.

President Obama and presumptive Republican nominee Mitt Romney are spending more money than ever on television advertising in crucial electoral battlegrounds, meaning that residents of Mansfield have been subject to the most intense political ad blitz in history.

Located almost equidistant between Cleveland and Columbus, and able to watch stations in both of Ohio’s top media markets, Mansfield’s TV viewers were subject to more than 12,000 presidential political ads in July alone, from the campaigns and from political action committees aligned with them.

This unprecedented pace — nearly 400 ads per day, or 16 every hour — is double that of July 2008, underscoring how enormous sums of money have changed the nature of the 2012 race.

On Wednesday, Obama appeared before about 2,100 people at a campaign rally in Mansfield before heading to nearby Akron for a second event. His appearance was previewed Tuesday evening by — what else? — new attack ads from each side.

“Unless you’ve been hiding from your television, you might be aware there’s an intense campaign going on right now,” the president deadpanned at the start of his remarks.

His newest ad, titled “Worried,” attacks Romney for proposing tax cuts for millionaires and new military spending that would drive up the deficit — a message that dovetailed with Obama’s remarks at the rally.

“The bulk of his tax cut would go to the very top, a lot to the wealthiest 1 percent,” he said.

So far, the Obama campaign has outspent Romney in Ohio, accusing him of outsourcing jobs overseas while at Bain Capital and demanding that he release more of his tax returns. The ads seem to be helping Obama; a new Quinnipiac University-CBS News-New York Times poll shows him leading Romney 50 percent to 44 percent in Ohio.

The advertising has filled the coffers of television executives — Cleveland ranks second in the nation in political ad spending, and Columbus ranks eighth — and made it virtually impossible for local residents to escape the daily infighting. The 7 p.m. to 8 p.m. block Tuesday on Cleveland’s WKYC, an NBC affiliate, was saturated with seven ads: two apiece from the campaigns, one each from the Republican and Democratic national committees, and one from Restore Our Future, a Romney-aligned super PAC.

“They all kind of bleed together. They’re all kind of malicious,” said Aurelio Diaz, 36, of Mansfield, who works at a center for disabled people and describes himself as politically independent.

While watching the Olympics this week, Mansfield Mayor Timothy Theaker (R) said, he saw a presidential ad during almost every break. “It’s an eye-opening experience . . . to see all the negativity,” he said.

The ads track closely with the daily campaign, with both sides playing off news events (a new pro-Romney spot features Olympic gold medal figure skater Kristi Yamaguchi endorsing him) and trying to exploit their opponents’ records and gaffes.

Romney’s newest ad, titled “Dream,” says Ohio car dealerships “were forced to close” in the wake of the Obama administration’s 2009 bailout of the U.S. auto industry. The spot features a man who had to shutter his GM dealership in Lyndhurst, outside Cleveland.

Obama has said the bailout saved jobs and helped General Motors and Chrysler rebound from near-bankruptcy, and that message has played well in heavily unionized areas of northeast Ohio. But here in Richland County, where Obama lost in 2008, 56 percent to 43 percent, the president could be more vulnerable.

A General Motors plant in Ontario, a town that borders Mansfield, closed in 2010, eliminating 1,200 jobs. The shuttered plant, surrounded by a barbed-wire fence, is in the process of being bought by a developer. But previous attempts to redevelop it have fallen through, said Gary Utt, a Democratic county commissioner who worked for GM for 26 years.

Across the street, Josh Mueck, 35, who owns a tractor equipment company that employs four people, said Romney’s recent ad attacking Obama for saying “you didn’t build that” while talking about small-business owners struck a chord.

“That showed me what I always believed” about Obama, Mueck said. “His belief in the collective, that every idea belongs to society instead of to the person.”

But Chris Elswick, 47, a school board member who supports Obama, called the ad an “outright lie” that was “edited together to look like he was saying something negative about small business.” Elswick, who owns an appliance repair company, said he found a longer version of the president’s remarks online that provided more context.

And Elswick has adopted a trick to escape some of the daily air assault.

“We live in a world of TiVo,” he said. “You record your show, and when the ads come on, you zip right through them. I honestly think at this point that 95 percent of people have made up their minds already anyway.”

T.W. Farnam contributed to this report.