Whisk together 3 tablespoons of olive oil, the lemon juice, wine, and garlic in a medium bowl. Toss the shrimp in the mixture. Cover and let stand in the refrigerator for 20 to 30 minutes.

In a large nonstick skillet, heat the remaining olive oil over high heat. Remove the shrimp from the marinade with a slotted spoon and add to the skillet. Cook for about 3 minutes, turning, or until bright pink. Remove the shrimp from the skillet. Add the marinade, marjoram and red pepper flakes. Reduce heat to medium and simmer for about 5 minutes.

Add the shrimp back to the skillet, season to taste with salt, heat through and toss with the parsley. Serve immediately.