While you can put two bulbs in series, and they should share voltage well, I'm not sure on these LED lights. I want to say "yes" but without knowing what is inside them, I don't know. Odds are, they just have a ballast resistor, in which case you should be fine. Actually, I think you'll be fine regardless, but I'd hate to myself wrong. I take it you have a mis-mash of parts, and are trying to get something to work?