This article is from the archive of our partner National Journal

It was just two weeks before Election Day and the money spent in North Carolina's Senate race, between Democratic Sen. Kay Hagan and Republican Thom Tillis, was closing in on the $100 million mark. A moderator asked a group of 10 "Walmart Moms"—female swing voters with children at home and who have shopped at Walmart in the last month—in Charlotte to say what they remember from the political ads they've seen.

The answer: silence. "I'm trying to think "¦ I've heard them 100 times," one woman said, trailing off.

"All I get from all of those [ads] is don't vote for that person because they're a bad person, vote for me," another woman said.

How many of the 10 women thought Hagan deserved reelection, the moderator asked? No hands were raised. How many thought she didn't deserve reelection? Still no hands.

"All those ads and you really don't know one way or the other?" the moderator said.

"I think we're just tired of hearing the bull crap," one woman said about the ads.

More than $1 billion has been spent on the airwaves during the 2014 midterms, pushing thousands of ads in front of voters in the states with the hottest Senate races. That's the biggest amount of ad spending ever for a midterm election.

But what does it matter if voters aren't getting the message?

Despite the unprecedented resources that campaigns, committees, and outside groups are pouring into this year's midterm elections, particularly in the battleground states where Senate control is likely being decided, those messages are diluted and drowned out for many voters. There are plenty of campaigns shouting their messages across the airwaves and voters are painfully aware that they're there—but it's not clear who's really listening.

Consultants on both sides of the aisle say there are a handful of reasons for the lack of recall on the part of voters: Some of them go numb and tune out after a while; others get lost in the sea of advertising and mix the messages up; others tune out as a symptom of their lack of faith in government overall. But despite the questions about how many ads are actively breaking through to voters, one thing is certain: Nobody's going to tone down the spending any time soon.

"People become numb to what they're seeing on TV when it's nothing but wall-to-wall advertising," said Neil Newhouse, the GOP pollster whose firm, Public Opinion Strategies, co-conducted the Walmart Moms groups. "It's difficult for them to distinguish between different ads, between the candidates and between the messages "¦ a lot of these voters, they can't wait for Election Day to be over with."

In the Iowa Senate race, for example, which has seen tens of millions of dollars in ad spending, a Quinnipiac poll released Monday found that 9 percent of likely voters still said they "hadn't heard enough" about Democrat Bruce Braley to say whether they viewed him favorably. Six percent said the same of Republican candidate Joni Ernst, despite her now-famous ad in which she describes "castrating hogs on an Iowa farm" while growing up.

Political ads have become "wallpaper," said GOP consultant Brad Todd. "Late ads have always mattered more but now "¦ you can't do anything new in the late stages unless you want to risk getting lost," he added.

Late-stage political ads could sway the tiny slice of voters who are still undecided until they walk into the polls on Election Day, so campaigns advertise straight through the end with everything they've got to reach those people on the off-chance they're your deciding votes, consultants said.

"Consumers pay attention to advertising right before they're about to purchase it," Todd said. "I love pickup trucks, and I only watch pickup truck ads when I'm about to replace my pickup truck. I couldn't tell you what's on a Ford F-150 right now to save my life."

Plus, Democratic pollster Mark Mellman said, voters often remember more than they think they do from the ads they've seen—whether it's the general tone of an ad or the way it made them feel about a candidate.

"There are a lot of things people know that they don't realize they know," he said. "Sometimes these things seep in in weird ways."

It's created even bigger problems for down-ballot candidates, who have nowhere near the money to compete with big Senate or gubernatorial races to get on the air. John Del Cecato, a Democratic media consultant at AKPD Message & Media, said one client, a candidate for Iowa secretary of state, has been up against "wall-to-wall" advertisements from the Senate race. His solution: to run a humorous, direct-to-camera ad with the candidate and his family.

"When you're participating in a down-ballot campaign and don't have limitless money, you have to try to stand out more with your creative," Del Cecato said.

Even though voters hate all the political ads, they're not going anywhere as long as campaigns think there's even the slightest chance they're persuading votes—so expect the increased volume of ads this year to be the new normal going forward.

"There certainly is a point of diminishing returns—but diminishing returns means there's still some returns," Newhouse said. "You do everything you can to try and turn that last voter, those last 100 voters, those last 1,000 voters to make a difference."

This article is from the archive of our partner National Journal.

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