October 1, 2024

A new ad testing poll from Blueprint indicates that 15-second ads are more effective on a per-second basis than longer spots at swaying voters toward Vice President Harris. 

In our latest ad test, Blueprint examined whether longer ads are worth the added cost by adjusting ad impact for length. For example, since a 60-second ad is four times as long and roughly four times as costly as a 15-second spot, shouldn’t it have four times the impact? 

The answer is a resounding no: the longer an ad runs, the less efficient it becomes at increasing support for Vice President Harris—suggesting that the best ads are short ones, which hit on broad messages instead of detailed policy plans.

Partnering with Van Ness Creative Strategies (VNCS), an award-winning political creative firm, Blueprint tested 15-second, 30-second, and 60-second ads across two themes: Harris’s economic policies to lower prices and her life story as it relates to her platform.

The ad test finds that 15-second ads move the needle towards Vice President Harris by an average of 2.3 percentage points per 15 seconds of airtime—compared to 30-second ads on the same topics, which only average a 1.5-percentage-point effect for every 15 seconds of airtime, and 60-second ads, which have an average 1.2-percentage-point effect per 15 seconds of airtime. 

In short, it is more cost-effective to run two 15-second ads about Harris in place of a 30-second ad or four 15-second ads in place of a 60-second ad. Running two 30-second ads is narrowly more efficient than running a 60-second ad. On an impact-per-second basis, 15-second ads are 53% more cost-effective than 30-second ads, and they are 92% more cost-effective than 60-second spots. Meanwhile, 30-second spots about Harris are 25% more cost-effective on a per-second basis than 60-second spots.

Among independent voters, the effect is even more pronounced; ads on Harris’s biography and economic policies boosted support by 4.9 and 4.5 percentage points, respectively, when shown in 15-second formats. In comparison, 60-second ads on the same topics achieved only a 2.1 and 2.2 percentage point increase with independents.

“Short and sweet ads that hit on broad-based messaging do the best job of persuading voters,” said Blueprint lead pollster Evan Roth Smith. “Voters simply want to hear more about Harris, and our findings show that they don’t need lengthy details to make up their minds, especially when it comes to key groups like independent voters. In the run-up to Election Day, the Harris campaign and Democratic PACs can be reassured that shorter ads will deliver more bang for their buck.”

ECONOMIC ADS

Blueprint tested ads highlighting Harris’s economic policies aimed at lowering costs for American families.

• The 15-second ad emphasized Harris’s commitment to fighting corporate price gouging, reducing healthcare and housing costs, and making the American Dream attainable for middle-class families. This ad boosted voter support by 2.1 percentage points, with a 4.5-point increase among independents.

NAME: 15-seconds: Economic policy

CREATIVE: VNCS

• The 30-second ad expanded on the same themes, adding details about Harris’s $25,000 credit for first-time homebuyers and her plan to cap prescription drug costs. This version moved support by 1.4 percentage points per 15 seconds, with a 2.9-point increase among independents.

NAME: 30-seconds: Economic policy

CREATIVE: VNCS

• The 60-second ad further built on the message, including policy specifics like a $6,000 Child Tax Credit, building three million new homes, canceling medical debt for millions, and capping prescription drug costs at $2,000. This ad led to a 1.1-point increase per 15 seconds and a 2.1-point gain among independents.

NAME: 60-seconds: Economic policy

CREATIVE: VNCS

LIFE BACKGROUND ADS

Blueprint also tested ads contrasting Harris’s middle-class upbringing with Donald Trump’s wealthy background and emphasizing her plans to fight for everyday Americans and lower prices.

• The 15-second ad highlighted how, while Trump lived off his inheritance, Harris worked at McDonald’s and knows the struggles of the middle class. This quick spot increased support by 2.5 percentage points, with a 4.9-point boost among independents.

NAME: 15-seconds: Biographical

CREATIVE: VNCS

• The 30-second ad hit on the same points but added Harris’s policy proposals, including her $25,000 credit for first-time homebuyers and her plans to protect Medicare and bring down the cost of medicine. It resulted in a 1.6-point increase per 15 seconds and a 3.0-point gain with independents.

NAME: 30-seconds: Biographical

CREATIVE: VNCS

• The 60-second version provided a more detailed picture of Harris’s public service, including her record as California Attorney General, where she won $20 billion for homeowners hurt by the mortgage crisis. The ad also highlighted additional policy proposals such as building three million new homes, giving parents a $6,000 Child Tax Credit, capping the cost of prescription drugs at $2,000 a year, and canceling medical debt for millions of Americans. This longer spot produced a 1.2-point increase per 15 seconds and a 2.2-point lift with independents.

NAME: 60-seconds: Biographical

CREATIVE: VNCS

ABOUT THE POLL

Blueprint surveyed an online sample of 7,997 voters from September 21 to September 23. Respondents were randomly exposed to no ad or a random one of the six VNCS ads.

Treatment effects were estimated through a regression model comparing control group respondents to treated respondents by ad, adjusting for pre-treatment covariates and estimated previous exposure to in-survey experiments.

The survey was conducted in English.

 The full suite of ads, created and produced by VNCS, can be accessed here.

ABOUT VNCS (Van Ness Creative Strategies)

VNCS is a digital agency and full-service creative studio focused on electing Democrats.

PRESS CONTACTS

Alyssa Cass
alyssa@slingshotstrat.com
347-992-5006

Evan Roth Smith
evan@slingshotstrat.com
646-240-0096

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