The Vermont senator's chances have dwindled from slim to virtually none over the course of the last several weeks, now giving way to Clinton reaching the magic number of delegates needed to win the Democratic bid.
The number of delegates that Clinton has amassed as of Monday night factors in 23 additional superdelegates, according to the Associated Press, bringing the total to 571.
According to the latest ABC News estimate, Clinton has 2,383 total delegates (1,812 pledged and 571 super) and Sanders has 1,570 (1,522 pledged and 48 super).
Here's what Sanders would need to win the nomination at this point:
Even with a wide victory in every state that votes tomorrow (by 20 percentage points) and picking up every remaining uncommitted superdelegate, Sanders would need to flip more than half of Clinton's superdelegates in order to win the nomination.
Sanders has often called the superdelegate process "absurd" and "pathetic" while bemoaning Hillary Clinton's substantial superdelegate lead.
In addition to her sweeping lead among superdelegates, more than 700 party officials who are free to vote however they choose, Clinton also holds a nearly 300-delegate lead among pledged delegates who were allocated based on primaries and caucuses.
In order to lead in the pledged delegate count, Sanders would need to win each remaining state by a whopping 41 percentage points.
The Democrats' proportional allocation system has made mounting a comeback nearly impossible, giving roughly the same number of delegates to a state's winner and loser if the final tally is very close.
Sanders said Monday night in a statement that the new delegate count is "ignoring the Democratic National Committee’s clear statement that it is wrong to count the votes of superdelegates before they actually vote at the convention this summer."
Sanders' camp vowed that he will go after Clinton's superdelegates.
And the Clinton camp, while saying it was "flattered" said that it was focusing on the primaries in six states Tuesday with hundreds of delegates at stake.