PHOENIX – Terri Briggs is a voter living at the deafening epicenter of the 2018 campaign.

Her community, Phoenix, has seen more political ads since Labor Day than any other TV market in the country.

"I’m sick of it," she said. "I don’t even like to watch TV. I’m muting it constantly because I can’t stand to hear the political advertisements."

More than 41,000 political spots aired on broadcast television in Phoenix between Sept. 3 and Oct. 16, according to data provided to the USA TODAY Network by Kantar Media/CMAG, a nonpartisan firm that tracks advertising.

By this measure, TV viewers in Phoenix have been more saturated in politics than anywhere in the nation.

Rounding out the top 10 advertising hot spots are Las Vegas, Tucson, Tampa, Minneapolis, Orlando, Denver, Los Angeles, Reno and Miami, where collectively more than $300 million has been spent since Labor Day on broadcast TV by candidates, parties and groups, according to the Campaign Media Analysis Group (CMAG).

These are the places where the most frenzied political fights in America converge, where costly state and federal races and even multimillion-dollar ballot battles have combined to hijack viewers’ television screens.

It’s all taking place in an overheated election year in which broadcast TV advertising for congressional and gubernatorial campaigns is up significantly over the previous midterm, according to the Wesleyan Media Project.

"For all the talk of the decline of television (ads), we really are not seeing any evidence of it in 2018; in fact, quite the opposite," said Wesleyan University political scientist Erika Franklin Fowler, citing among other reasons the sheer competitiveness of this election cycle.

The ad wars in these top 10 markets feature some of the nation’s hottest races for US Senate (Arizona, Florida, Nevada), governor (Florida, Nevada) and U.S. House (Minnesota).

But they also include myriad referenda over issues from gambling to rent control to animal welfare; lavish state legislative battles; and lower-budget, down-ballot races for offices such as mayor and sheriff.

Phoenix is an example of the convergence of political forces. About three-quarters of the nearly $40 million in broadcast TV spending it has seen this fall involves three items – the contests for U.S. Senate and governor and the most fiercely fought ballot measure in Arizona history. It would require electric companies to get half their power from renewable sources such as solar and wind by 2030. The ballot question pits the parent company of Arizona Public Service Co. against a group funded by California billionaire activist Tom Steyer.

But adding to the din are less costly contests for attorney general, mayor, secretary of state and state superintendent of public instruction; four U.S. House races; and a ballot fight over taxing power.

Here are two examples of the saturation-level of the air wars from one recent day in the campaign (Oct. 16) in Phoenix: during a 30-minute local news broadcast on KSAZ-TV, the Fox affiliate, viewers saw 14 different political ads. On a four-hour “Good Morning Arizona” broadcast on KTVK-TV that same day, they saw 71 political ads, according to CMAG.

Santiago Feria, a Republican retiree from Mesa, tries to shrug off the nonstop political messaging.

"It’s just part of the season," he said. "I really don’t like the attack ads, but that’s part of the game."

Los Angeles has seen almost $50 million in ads on ballot measures alone, including proposals to expand rent control, curb dialysis profits, repeal a gas tax hike and encourage more humane cages and pens for farm animals such as pigs, calves and chickens.

In Las Vegas and Reno, the wall-to-wall ad wars feature two of the nation’s tightest races for U.S. Senate and governor. But they also include four Nevada ballot questions, led by a fight over regulation of the state’s power industry that has generated more than $13 million in broadcast ads in those two TV markets since Labor Day.

Three Florida markets are in the top 10 – Tampa, Orlando and Miami – a byproduct of that state’s marquee races for governor and Senate as well as two costly ballot battles over gambling and victims’ rights.

For Adelaide Liverpool, who has lived in Orlando for a little over seven years, exposure to political ads has become routine. Whether it be billboards, radio or television ads or sign-wielding volunteers across her apartment complex, she can’t get away from political messaging.

“It’s very annoying, I don’t need it,” Liverpool said. “I know what I have to do.”

In Colorado, Denver is home to a red-hot congressional race and has seen almost $8 million in broadcast ads for five different statewide ballot measures, led by an anti-fracking initiative requiring major new setbacks on oil and gas projects.

In Minnesota, the Twin Cities are one of the nation’s top battlegrounds in the battle for the U.S. House. More than $20 million has been spent on broadcast TV ads in that market on four different congressional races since Labor Day.

After the Top 10, the next tier of advertising hotspots include Kansas City; Sacramento; Fresno, California; Detroit and Grand Rapids, Michigan; Milwaukee; Portland, Oregon; Chicago; Green Bay, Wisconsin, and Philadelphia.

According to the Wesleyan Media Project, the volume of political advertising is up 110% over 2014 in U.S. House races and 70 percent in contests for governor (comparing the period from mid-September to mid-October in each cycle).

"No doubt people spend too much money on TV. But when you get into a campaign and you have more money and you’re trying to decide what to do with it, broadcast TV is a very attractive place to put it," said Will Feltus, a GOP ad buyer and co-author of the book, "Inside Campaigns," a compendium of interviews with more than 100 campaign managers about how political campaigns are conducted.

Take the USA TODAY Elections Quiz here.

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Contributing: Ana Ceballos, Naples Daily News