HALPERIN'S TAKE: Why Hillary Clinton is Determined to Fight On

1. She thinks she would be a better president than Obama.

2. She thinks she would be a stronger candidate against McCain than Obama.

3. She feels an obligation to her supporters to keep fighting.

4. She thinks she can win Pennsylvania.

5. She thinks she is finally gaining traction on the “national security experience” argument.

6. She thinks the one-on-one debate has only just begun, along with the heightened scrutiny of Obama.

7. She is finally raising enough money to fight the fight with paid TV ads.

8. She knows the Rezko trial is getting started.

9. She knows Obama is still well short of winning a majority of the delegates.

10. Clintons don't quit--and she really, really, really wants to win.