In the United States, political campaigns use data on more than 200 million voting-age Americans to inform their strategies and tactics.
The two major U.S. parties compete to use the most accurate data to target voters in various ways, an edge that was touted as key in former President Barack Obama and President Donald Trump’s election victories.
Republicans and Democrats work with data firms to create national databases of voter files, collecting information from many sources to create detailed profiles of voters with thousands of data points and build models that predict people’s stances on issues or candidates.
Political campaigns can use this data to help decide whom to target in their outreach efforts, how to reach them and how they might respond to certain messages.
The U.S. “voter file” is not one national database. The information used by the campaigns is collected from many public voter files, layered with hundreds of data points bought from commercial vendors, and updated regularly by firms like TargetSmart, which works for Democrats, and Data Trust, which helps Republicans.
Political data firms buy data from companies like Experian or Acxiom, which can include real estate property records, estimated income levels, consumer purchasing patterns and demographic data including likely race and ethnicity.
These types of data are some of the ingredients in the predictive models that campaigns use:
Predictive models can inform campaign decisions about how to target voters by predicting how likely people are to:
- Support a particular candidate
- Demonstrate certain behaviors or fit lifestyle profiles, such as attending church, using social media or having medical insurance
- Think a certain way about topics like gun control, same-sex marriage, race, the environment or the Supreme Court
- Change their positions due to various campaign efforts
For example, a candidate might want to not spend money targeting staunch supporters with persuasive Facebook ads – but they might want to text them to remind them to vote. Or a campaign might decide to emphasize its healthcare policy to people who have voted for the opposing party in the past but who are worried about health costs.
Here is how predictive models are built:
Models aren’t enough
Campaigns gain valuable and reliable data when people answer a volunteer’s door-knock or call, sign a petition from a Facebook ad or go to a rally. They also use their databases of phone numbers to push out tens of millions of text messages and log numerous details from those responses.
“Asking someone is better than any data modeling you’re ever going to find, so what the data modeling does is help you figure out who are the right people to ask,” said Colin Delany, a digital consultant.
As the Nov. 3 election nears, campaigns also use state data to track who has requested an early or absentee ballot and who has returned it, so they can chase people up to vote – and not waste time contacting someone who has already voted.
Campaigns use data to inform decisions about everything from where to send mailers, which places candidates should visit and where to buy or target TV ads. They can also use it to “microtarget” political ads to voters on social media and online platforms.
On Facebook, campaigns can upload a list of people they want to target using details like names or phone numbers. They will be told how many of those on the list saw the ad, but not who they are. They can also target people similar to their list.
Campaigns can also target Facebook users by layering multiple data points, like whether they have adult children, are interested in electric cars or use a language not common to their locations – and they can target by location down to a 1-mile radius. Search Facebook’s ad library here.
How campaigns access and use social media data to target voters came under greater scrutiny following now-defunct data firm Cambridge Analytica’s improper use of Facebook users’ personal data.
Google and YouTube have limited audience targeting for election ads based on age, gender and postal code, so candidates can’t target using public voter records, political leanings or their own lists of people. Both Facebook and Google have announced temporary pauses on political ads around the November election, while Twitter and TikTok do not allow political ads.
Campaigns may have different agreements with the political parties about sharing the data they collect but many will feed data back into a central system to improve the overall voter file.
Data Trust, a private company started in 2011 which has an exclusive agreement with the Republican National Committee (RNC) , also facilitates data exchanges between Republican committees and organizations.
As part of efforts to overhaul Democratic data operations following Trump’s win, the Democratic National Committee (DNC) and Democratic state parties agreed to participate in the Democratic Data Exchange. This separate company now allows committees, campaigns and outside political groups like labor unions or super PACs to trade the information they get from contacting voters in a central file.