3. -c6 4. Nc3 would be a transposition of the Marshall Gambit: 1. d4 d5 2. c4 e6 3. Nc3 c6 4. e4.
3. -c5?! 4. cxd5 exd5 5. dxc5 d4 6. Bc4 Qa5+ 7. Bd2 Qxc5 8. Qb3 Qc7 9. Ne2 Bc5 10. O-O Nc6 11. Na3 with slight advantage for White (Schwarz in his book Die Franzosische Verteidigung).
3. -Nf6 4. Nc3 Nxe4 5. Nxe4 dxe4 6. f3 Nc6 7. d5 exd5 8. cxd5 Bb4+ 9. Bd2 e3 10. Bxb4 Nxb4 11. Qa4+ Nc6 12. O-O-O Qg5 13. f4 1-0, Gedult - Sachs, Paris 1950.
4. Nc3 c6
4. -Ne7 5. Bg5 c5 6. cxd5 O-O 7. Nf3 exd5 8. e5 cxd4 9. Qxd4 Nbc6 10. Qh4 Be6 11. Bd3 h6 12. O-O Qd7 13. Rad1 Ng6 14. Bxg6 fxg6 15. Bc1 Rf5 16. Ne4 Rh5 17. Qg3 Bg4 18. Nh4 Bxd1 19. Rxd1 Nxe5 20. Nxg6 Nxg6 21. Nf6+ gxf6 22. Qxg6+ Qg7 23. Qxh5 Kh7 24. Qxd5 Re8 25. Be3 b5 26. Qf5+ Kh8 27. Rd7 Re7?? 28. Rd8+ 1-0, Bachl - Wolter, Germany 1956.
5. a3 Ba5 6. b4 Bc7 7. Nf3
7. Bb2 dxe4 8. f3 would have been the last try to get a pure gambit.
7. -dxe4 8. Nxe4 Nd7 9. Bg5 Ngf6 10. Bd3 h6 11. Bh4 O-O 12. Bc2 Qe8
12. -g5 13. Bg3 Nxe4 14. Bxe4 f5 15. Bxc7 Qxc7 16. Bc2 is unclear.
13. Qd3
13. Nxf6+ Nxf6 14. Qd3 g5 (14. -e5 15. dxe5 Bxe5 16. O-O) 15. Nxg5 (15. Bg3) hxg5 16. Bxg5 Kg7 17. Qf3 Qe7 18. Bxf6+ Qxf6 19. Qg4+ Kh6 20. Qh3+ Kg5 21. g3 Qh8! 22. f4+ Kf6 23. Qg4 =+.
13. -Nxe4 14. Qxe4 g6
14. -f5 15. Qe3 g5!? (15. -Qf7) wins a Bishop, and White should not get more than a few checks.
15. Ne5 Nxe5 16. dxe5 Bd8 17. Bf6 Bxf6 18. exf6 Qd8 19. Qf4 Kh7
19. -e5 20. Qf3 (20. Qxh6 Qxf6 21. h4 is probably better) Qd4 21. O-O Bg4 =+.
20. h4 e5
20. -h5 21. Qg5 Rh8 (21. -Qd4 22. Qxh5+ Kg8 23. Bxg6 1-0) 22. Qxh5+ Kg8 23. Qg5 Qd4 (23. -Rh5 24. Qf4) 24. Bxg6.
21. Qf3 Re8
21. -Qd4! 22. Rd1 Bg4 (22. -Qxc4 23. Be4) 23. Rxd4 Bxf3 24. Rd7 Bxg2 25. Rh2 Bf3 26. h5 is unclear.
22. h5 e4 23. hxg6+ fxg6 24. Qf4 h5 25. Qg5 Qd4
25. -Bf5 26. Rxh5+ Kg8 27. Rh8+ Kf7 28. Rh7+ Ke6 29. Rd1 Qc8 30. c5 1-0.
26. Rxh5+ gxh5 27. Qg7#