Facebook's new searchable database of U.S. political ads reveals that companies such as Exxon Mobil, Ben & Jerry's, and Penzeys Spices are cumulatively spending millions of dollars to encourage voting and influence how Americans vote.

Little data is typically published on specific companies' online ad spending, but Facebook's increased transparency about political activity on its service has opened a trove of details ahead of elections on Nov. 6. The social media network showed that $256.4 million was spent on political ads since May.

Alphabet's Google and Twitter have introduced similar databases. But compared to Facebook, Google covers a narrower set of advertisers and Twitter's tool is more difficult to use.

The database unveiled by Facebook on Tuesday, called the "Ad Archive Report," will provide weekly updates on how much advertisers are spending on Facebook ads that specifically, encourage voting or mention political races or issues of national importance.

That policy pulls in ads from official campaigns as well as paid posts containing a political dimension from boutique apparel makers, talk-show hosts and global firms.

Oil giant ExxonMobil has spent more than $2.1 million on Facebook ads since May, more than any corporation beside online petition service Care2.com. ExxonMobil has promoted a campaign supporting offshore drilling and urged a "no" vote on a Colorado ballot measure that would limit fracking.

The company did not immediately respond to a request to comment.

Ben & Jerry's, a part of Unilever, has spent more than $401,000 since May on various ads, including one supporting a Florida ballot measure that would let felons vote.

Jay Tandan, the ice cream maker's U.S. digital marketing manager, said the company welcomed the transparency.

"Weve long stood up for our company values and used our tools as a business including monetary expenditure and our social media presence to support driving the change we hope to see in the world," Tandan said in an email.

Penzeys, a nationwide retailer of spices based in Wisconsin, has put $773,000 into ads calling on people to vote despite any political frustration they may have following the contentious Senate confirmation of Supreme Court Justice Brett Kavanaugh.

"Make your plan to vote, but please give thought to encouraging others to vote, too," one ad seen by at least hundreds of thousands Facebook accounts said. "Help them put together the ingredients they need for a healthy and satisfying voting experience."

Smaller firms are aiming to capitalize on the election too. California-based Concealed Online, which sells firearms training for concealed carry permits, has spent $1.76 million encouraging people in Texas, Florida and other states to apply before a possible shift in power brings gun restrictions.

To be sure, Facebook's transparency has limits. It privately requires government-issued identification from political ad buyers but allows them pseudo-anonymity in public disclosures through vague names such as Be Registered.

The tech companies' political spending databases arrived after the threat of regulation over the lack of disclosure on such spending.

Facebook also has faced a barrage of criticism from users and lawmakers after it said last year that Russian agents used its platform to spread misinformation before and after the 2016 U.S. presidential election, an accusation Moscow denies.