Clinton:

1. New York, California, New Jersey, Connecticut, Ohio, and Texas

2. A sustained national polling lead

3. Closed primaries in which only Democrats vote

4. Perceived experience

5. White, Hispanic, and low-income voters

Obama:

1.  “Bush-Clinton-Bush-Clinton” will never sound like change

2.  The media is (passionately) on his side

3.  Maryland, Virginia, Wisconsin, and caucus states

4.  Internet money

5.  A loyal, ardent, focused staff
McCain:

1. The national security card

2. The media is (cozily) on his side

3.  Experience

4.  Open primaries

5.  Gov. Charlie Crist

Romney:

1. His (still vast) bank account

2. Virulently anti-McCain Republicans who will champion him by default in a one-on-one race

3.  The rising salience of the economic issue and his crisp CEO argument

4.  Talk radio

5.  Vigor and acute drive