Political advertisements on social media are nothing new, however, in this election, there is a way to track who is paying for what.
So far candidates, political action committees (PACs) and other outside groups have spent more than $16 million in Facebook ads, according to the social network's ad library report.
Between his campaign and PAC, Democratic presidential nominee Joe Biden has spent $2.4 million in Facebook ads specifically targeting Wisconsin voters. President Donald Trump's campaign and PAC have spent $1.6 million.
But the two candidates combined only account for 25 percent of all the ad spending towards Wisconsin voters. The other three quarters are coming from outside groups.
University of Wisconsin-Madison professor Young Mie Kim has researched outside groups spending big bucks on social media. She tracked spending back to Russian groups in the 2016 election.
She says four years later, Facebook is a little more transparent about where the money is coming from.
They have made the ad library public, and those Facebook pages running ads have to disclose who paid for it. But it's not perfect.
"The current pay verification system has a lot of loopholes, for example, you can just type in whatever domain you want and they just bypass those a transparency measures," Kim said.
It can have consequences if you don't know who is really behind the ad.
"They can disguise the ads you know inside a group," Kim said.
"It looks like two seconds of self-criticism, healthy criticism, but in fact, it could be an attempt to suppress turnout from the opposition," she also said.
So far this election season, posts about the election itself dominate the ad space for Wisconsin Facebook users. That's according to research done by New York University's ad observatory.
Elections outrank both candidates as well as the coronavirus in the top five topics of Wisconsin advertisements.
The Facebook Ad Library publishes the top 10 spenders in the last 90 days. Here's a look at each of those groups.
9. Future Majority
Paid for by Future Majority, Inc.
Spent $265,079 from July 12 to Oct. 12
Future Majority is a political non-profit and is exempt from FEC filings.