recommendations for dry red wine
The bad news is that "dry red wine" describes at least 25-40% of the bottles at an typical wine shop.
The good news is that she would probably enjoy ANY nice example of such widely available varietals as merlot, cabernet, zinfandel, or shiraz, and most red varietals from Italy, Spain, Australia, or South America...
So pick your price range and then ask the wine shop for what would be the best of the above type wines in their inventory at your price.
If you ask her and find out what one of her favorite wines is, and/or if you know what type of food will be served at this party, then you could narrow it down much more.
Anything more specific? It's a bit like saying "the host likes food, what should I bring?" There are literally tens of thousands of possibilities. Do you know if she likes -- for example -- California reds, French reds, Italian reds? Do you know if she likes Cabernets, Zinfandels, Pinot Noirs?
Does she like to cook any particular type of food -- say Italian, or vegetarian -- more often than others?
And what are you comfortable in spending? You can find nice wines to fit any budget, but there is little point in suggesting, say, a wine that costs $100 if you only want to spend $15.