__________ to __________ IV

Each clue below can be answered using the same two words in an expression  in the form of ________ to ________.

For example, given the clue IN A CONFRONTATIONAL MANNER, the answer could be Face to face.

1. Type of intense combat
2. Canvass a neighborhood, as for sales (with GO)
3. Intimate conversation
4. Flight from LA to NY
5. Very crowded
6. Things lined up one directly behind the other
7. In agreement (with SEE)
8. Completely covered, as carpet on a floor
9. In a confrontational manner
10. In direct competition (with GO)

Answer:

1. Hand to hand
2. Door to door
3. Heart to heart
4. Coast to coast
5. Elbow to elbow 
6. End to end
7. Eye to eye
8. Wall to wall
9. Toe to toe 
10. Head to head