Looks like it depends on your efficiency. Comparing Austin Homebrew's cheapest bulk 2-row vs bulk extra light DME, you can buy 2.9lbs of 2-row per pound of DME. 1lb of DME in a 5 gallon batch will yield an OG of 1.009. Assuming a brewhouse efficiency of 45%, you will get 1.009 out of 2.9lbs of 2-row. Any higher efficiency and AG is cheaper. There are a few complications, though:
1. Darker extracts cost the same amount as the Extra Light. They will already include body-increasing specialty grains like various Crystal malts, so if you are fine with using the darker DME instead of buying separate steeping grains the cost of AG will raise as opposed to the cost of extract for a given recipe.
2. I just used prices off of Austin Homebrew for a comparison. It is possible you could find extract of 2-row for cheaper for a given recipe at another retailer. It is certainly possible to buy bulk DME and 2-row straight from the wholesaler for a cheaper price.