WATCH: Lawrence O’Donnell explains why Elizabeth Warren may be tied with Joe Biden for first place
MSNBC's Lawrence O'Donnell /Screenshot

MSNBC anchor Lawrence O'Donnell on Tuesday explained to his viewers why Sen. Elizabeth Warren (D-MA) may be tied with former Vice President Joe Biden in the race for the 2020 Democratic Party convention.

"New polling showing a possible statistical tie for first place in the democratic candidates between Joe Biden and Elizabeth Warren," O'Donnell reported.

"You have not heard that before because most polls in political campaigns ignore the margin of error. The margin of error in this new NBC poll is 4.9 percent -- just about five points as a margin of error. Joe Biden has a seven-point lead in the poll. That appears to be outside the margin of error, but it isn’t," he explained.

"Joe Biden at 26 and Elizabeth Warren at 19. What you have to remember about the margin of error is it means any number in the poll could move five points, in this case 4.9 in either direction, up or down. They can be independent. Joe Biden’s number could move down and Elizabeth Warren’s number could be higher in reality and there could be a spot in there and the truth is inside the margin of error where they are in a tie," he continued.

"Possibly even Elizabeth Warren is a point ahead. That’s how close this is. I know it might sound confusing, but that’s how margins of error are polling. What you are seeing is this real tightening between Joe Biden and Elizabeth Warren in that possible statistical tie for first place," O'Donnell said.

"This obviously puts enormous pressure on the next round of debates. The biggest movement in the polls since the first round has been with senator Elizabeth Warren and Kamala Harris. If they are perceived as they were before to be the winners of the next round of debates, it won’t be the end of Joe Biden or any of the other top tier candidates, but it could be enough to end the hopes of some of the bottom polling candidates," he added.