In almost every US Presidential Election, the winner of the national popular vote also won the Electoral College. What happened in 2016 was extremely rare, as while Clinton received 2.87 million more votes than Trump did, Trump received the majority in the Electoral College. Actually, in the 2016 US Presidential Election, ten members of the Electoral College voted for a candidate different from the one to whom they were pledged.
This happened just five times in American history, but twice in the last 16 years, the other time being George W. Bush's Electoral College defeat of Al Gore in 2000. In the US Electoral College system, each state gets a certain number of electors based on the total House and Senate representatives in each state's congressional delegation. According to many political experts, the problem is that the Electoral College weights the election in favor of small, rural states. The picture above shows that smallest-population states have three elctoral votes, while California, the largest, has 55.
With regard to US popular vote, which will be held next week, the poll found that Joe Biden hold an 8-point lead over Trump nationwide, 52 % to 44 %:
As it is known, Russia's intelligence services conducted cyber operations against targets associated with the 2016 US Presidential Election.
(source: https://www.dni.gov/files/documents/ICA_2017_01.pdf )
I do hope this time Russian Government doesn't order an influence campaign aimed at 2020 US election.