Facebook co-founder Dustin Moskovitz’s $20 million (âRs133 crore) pledge would make him the third biggest donor in the 2016 election cycle.
The billionaire says he is giving $20 million to help defeat Donald Trump, calling the Republican presidential candidate divisive and his appeals to Americans who feel left behind "quite possibly a deliberate con."
By contrast, Dustin Moskovitz says Democrats and their nominee, Hillary Clinton, are "running on a vision of optimism, pragmatism, inclusiveness and mutual benefit."
Moskovitz wrote about the contributions in a Thursday night posting on the website Medium.
"As a nation, we need to figure out how to bring everyone with us, and we believe the Democratic platform currently is more aligned with ensuring that happens," he wrote.
"In comparison, Donald Trump's promises to this group are quite possibly a deliberate con, an attempt to rally energy and support without the ability or intention to deliver. His proposals are so implausible that the nation is forced to worry that his interest in the presidency might not even extend beyond winning a contest and promoting his personal brand."
Moskovitz said he and his wife, Cari Tuna, are giving half of their $20 million to the League of Conservation Voters and to the For Our Future political action committee. The latter group is a get-out-the-vote effort in battleground states that is paid for primarily by labor unions and hedge fund billionaire Tom Steyer.
Moskovitz and Tuna also are giving directly to Clinton's campaign and to party committees helping Senate and congressional Democrats, he said.
Moskovitz's political giving makes him the second-largest Democratic contributor of the election, after Steyer.
(With inputs from AP