Here is the easy way. Wait until fall and it dies. Im in Iowa so it dies here anyway. It's crabgrass, and it will turn purple around the time you are doing your fall aerate and seeding. Seed the crap out of the lawn and cover with straw and have a better 2014 with PE. Some of the better spray techs can tell you how to get going faster, but it's $$ and a real tough job this late in the year. Spend the time with the fam and put this off until fall. It's nature and sometimes it will win.
I hate crabgrass, but my lawn is now thick KBG and a touch of Rye and there is no room for anything else. I barely spot sprayed with some old 2,4-d this year and it's nice. 4 years ago it was a disaster when we bought this place.