Again, the answer is yes. Outdoor landscape fixtures, path-lights, deck lights, step lights, etc typically operate off transformers to convert your household 120V line voltage to usually 12 volts. Landscape 12 volt LED bulbs are readily available and only consume about 2.5 to 4 watts or so.
This means more fixtures can be on-line with your transformer and you will enjoy extreme long life and excellent light output and color. It's just a matter of changing the bulbs to LED's.
Landscape bulbs are rather small with usually bi-pin or wedge bases and many utilize MR-16 lamps also. At BuyRite LED, there is a large selection of LED landscape bulbs. Another benefit is that LED bulbs actually like the cold……..so no worry in winter months. You can also add color to your outdoor lighting with colored LED's.