In the 45 days between the beginning of September and Oct. 15, Moskovitz and others donated a total of $66 million to Future Forward, a pro-Biden super PAC with a strategy focusing on TV spots late in the election season, according to Vox's Recode.

According to figures that are expected to be reported to the Federal Election Commission Tuesday, Moskovitz contributed at least $22 million during this time period. This is on top of the $1 million that FEC records show he gave to Future Forward in July.

Moskovitz has extensively researched how to have the greatest impact on voters, and along with Future Forward believes getting a strong message out right before people vote is the best way to do it, Recode reported.

The group tested ads throughout the year before pulling the trigger on their television campaign, which includes more than $100 million in ads between late September and Nov. 3.

Other big donors contributing to Future Forward's late-game push reportedly include Twilio founder Jeff Lawson and former Google CEO Eric Schmidt.

The ad spending comes as Facebook and Twitter have faced criticism for censoring a New York Post story on Hunter Biden's purported emails.

Future Forward's plans are not limited to the presidential race. According to a memo to donors obtained by Recode, they are teaming up with four other groups including Senate Majority PAC to fund an ad campaign supporting Democrat MJ Hegar, who is challenging Republican Sen. John Cornyn for his Texas Senate seat."

Based on an extensive analysis undertaken by Future Forward PAC and Senate Majority PAC (SMP), we believe that Democrats have a plausible chance to flip the TX Senate seat with a major financial investment in the race over the next week,” the document said. "We can push the odds of victory up significantly—from 23% to 35-55%—by blitzing the airwaves in the final two weeks."