Chocolate, of course, tends to be sweet. To pair with a red wine takes some creativity, and sticking with dark chocolate will help. Dark chocolate is much less sweet than milk chocolate, and might pair well with a red toward the fruitier end of the spectrum. A fruity red Zinfandel would work nicely, or, if you can find one, a Cabernet Sauvignon that leads with berry flavors and isn’t too dry.
A dark chocolate and red wine pairing has something beyond flavor going for it: both are considered heart-healthy food items.
If you absolutely must go with milk chocolate, a dessert wine like a Sherry or Ruby Port would work best. You might try a Merlot from the sweeter end of the spectrum, though I’d expect the creamy sweetness of the chocolate to clash with even fruity Merlots and Syrahs.
Of course, if you are giving a gift, you can always combine wine and chocolate even if you don’t plan to consume them side by side.