"This has been the world's longest job interview but we are getting down to the final decision," said Senator Hillary Clinton.
"If you will vote for me and stand up for me tomorrow, I promise we will not just win Pennsylvania, we will win this nomination. We will win this general election," said Barack Obama
For Clinton, winning here keeps her in the race. For Obama, a win puts him closer to clinching the democratic nomination. With the stakes so high, both campaigns have released a flood of negative campaigning like this new Clinton ad which features an image of Osama Bin Laden. She implies she's tougher than Obama.
Clinton, who appears today on Good Morning America, says would take an unwavering stance if Iran attacks Israel. "During the next 10 years, during which they might foolishly consider launching an attack on Israel, we would be able to totally obliterate them."
Obama, also on Good Morning America, defends his negative campaign tactics. "Somebody throws an elbow at ya, and after 3 or 4 times of getting elbows in the ribs, at what point do you say, ok, we've got to put a stop to that."
A big win here by either candidate could determine if the Democratic Party chooses its nominee sooner, rather than later.