I have these as well...got it as part of Decorative Dahlia mix from brecks. I too would like to know the name! Unfortunately yesterday's thunderstorms here in NJ broke half the plant and took a ton of buds and blooms along with it. This is my first year with dahlias and I have lot to learn...

Dave, that looks like Karma Choc to me, down to the green center. If you bought it at a nursery with rows and rows of potted dahlias, it's very likely. It could also be Kaisha Lee, introduced in 2011.

FowerFanatic, it's doubtful that your Breck grab bag had Karma Choc in it, as there is a licensing fee in order to propagate any of the Karma lines. Technically, it's illegal to even grow more then one in your own yard from year to year without paying the creator. It's one of the few dahlia breeding lines that the hybridizer protected propagation rights. It might well be Kaisha Lee, as Breck's has been expanding what they offer in terms of Dahlias.

There are more and more dark red dahlias coming into the marketplace, so its hard to tell from images alone. I would suggest to not trade/sell tubers of your unknown varieties as an assumed variety even when you are fairly sure. It is very disappointing when a tuber turns out to not be the variety it was labeled as, and serious collectors would be very put off by such an act.

hope this helps...

Below is a pic of my dahlia before it broke:

And here is another one from the brecks mix with a very similar flower color but an open yellow center.

3 other plants from the mix are just starting to show some buds.

Two more plants aren't showing any buds at all - one of which is almost 4 ft tall, other one is not doing so well (I posted the problem here)