Facebook Says 126 Million Users May Have Been Exposed to Russian PostsFacebook, Google and Twitter are set to testify before a congressional subcommittee on Russia's attempt to use social media to influence last year's election.

Russian efforts to influence American society over social media may have reached more than half of the country's voting population, according to new findings that'll be presented to Congress today.

Facebook, for instance, has found that 126 million users in the country may have been exposed to 80,000 divisive political posts written by a Kremlin-back Russian company, according toThe New York Times.

Twitter uncovered over 36,000 accounts possibly linked with Russia that generated 1.4 million automated election-related tweets, according to a source familiar with its upcoming testimony. Those tweets received 288 million impressions.

Google, on the other hand,found 1,108 videoson YouTube probably associated with a suspected Russian campaign to spread propaganda. The videos attracted 309,000 views in the U.S.

More details will be presented during today'scongressional hearingon Russian interference in last year's election. Representatives from all three U.S. tech companies are set to testify.

Facebook willreportedlydisclose that a Russian company called the Internet Research Agency controlled 470 accounts to publish the 80,000 posts. Those posts were served directly to 29 million users, and then liked, shared or followed by others, magnifying their spread.

Russia's Internet Research Agency, which isnotoriousfor being an Internet troll farm, alsospent $100,000 to display 3,000 adson the platform with divisive political and social messages, Facebook claimed last month.

Twitter also tracked over 2,700 users accounts to the Russian company, up from the 201 accounts it initially reported last month. All the accounts have been suspended. In addition, Twitter identified over 36,000 accounts found generating automated election-related content that possessed "at least one characteristic" associated with Russian user accounts.

Although the accounts produced 1.4 million tweets, that only represented 0.74 percent of overall election-related tweets during the Sept. 1 to Nov. 15 time period, according to Twitter's upcoming testimony.

Despite Facebook's and Twitter's attempts to crack down on the abuse, U.S. lawmakersremain concernedthat foreign governments will try to spread propaganda over their platforms in future elections. That may put Silicon Valley and Washington at odds over attempts to regulate social media.

However, both Facebook and Twitter are taking steps to add more transparency to their online political ad business, including who buys what. Last week, Twitterbanned two Russian media groupsfrom advertising on the platform over concerns they were spreading Kremlin-back propaganda.