It is true that Clinton polled mostly ahead of Trump in the 2016 election campaign, yet still lost the election. It is also true that Biden, while ahead of Trump in the polls today, could still lose to Trump this year even if he stays ahead in the polls all the way to election day.
But it is not true that Biden is in exactly the same situation as Clinton was in 2016. No, his situation is better and here's why as explained by Harry Enten.
"Almost any time I explain that Biden's leading Trump, someone will inevitably bring up "but what about 2016." That's why this week marks an important milestone for the Biden campaign.
It's one of the first times during the election year that Biden was clearly running ahead of Hillary Clinton's 2016 pace in the matchup against Trump.
Four years ago, Trump closed the national gap quickly with Clinton as he was vanquishing Republican rivals Ted Cruz and John Kasich from the presidential race. Clinton's average lead shrank from 10 points during the first half of April to 6 points in the second half in April to 4 points in the first half in May to a mere 1 point in polls completed four years ago between May 16-May 23....
Although Clinton would regain some of her advantage in June 2016, the fact that the race became so close at this point four years ago was an indication that the electorate was somewhat unsettled. It showed that under the right circumstances, Clinton could lose nationally, or, at the very least, that Trump could come close enough nationally to win in the electoral college....
Biden's lead, of course, is the steadiest of all time. His lead has never fallen to just a point or anywhere close. It's been consistently at or right around 6 points, as it was this week. If you were to create a 95% confidence interval around the individual 2016 and 2020 polls, the 2016 race was about 1.5 times as volatile up to this point.
But it's not just the margin that is important to examine. Look at the vote percentages.
The reason Biden's lead is so wide compared to Clinton's is that he's running a little more than 5 points ahead of where Clinton was in terms of vote percentage. Biden is at slightly greater than 48%, while Clinton was a little less than 43%.
Even when Clinton's lead widened in June, she never got to 48% in the polls. She had to pick up a lot more late-deciding voters for her lead to feel secure than Biden will likely need to."
2020 is not 2016. Biden is not Clinton. And the differences between the two situations and candidates mostly help the Democrats. This is worth keeping in mind the next time you hear "But 2016!"