Hopefully this clears things up. Vote away!
Closer
LEADING: Jude Law, Clive Owen, Natalie Portman, Julia Roberts
Collateral
LEADING: Tom Cruise, Jamie Foxx
SUPPORTING: everyone else
Dogville
LEADING: Nicole Kidman, Paul Bettany
SUPPORTING: everyone else
Eternal Sunshine of the Spotless Mind
LEADING: Jim Carrey, Kate Winslet
SUPPORTING: everyone else
Garden State
LEADING: Zach Braff, Natalie Portman
SUPPORTING: everyone else
I Heart Huckabees
LEADING: Jason Schwartzman, Mark Wahlberg, Jude Law, Naomi Watts, Dustin Hoffman, Lily Tomlin, Isabelle Huppert
SUPPORTING: everyone else
Kill Bill Vol. 2
LEADING: Uma Thurman
SUPPORTING: everyone else
The Life Aquatic With Steve Zissou
LEADING: Bill Murray
SUPPORTING: everyone else
Ocean's Twelve
LEADING: Brad Pitt, George Clooney, Catherine Zeta-Jones
SUPPORTING: everyone else
Sideways
LEADING: Paul Giamatti, Thomas Hayden Church
SUPPORTING: everyone else
Catwoman
LEADING: Halle Berry, Sharon Stone
SUPPORTING: The French guy from The Matrix Reloaded.