Governor Dean called the Dean Dozen "the progressive movement’s best chance at taking back Congress."

The first "Dean Dozen" was announced on May 13, 2004. Governor Dean eventually announced a total of six groups of 12 candidates to receive significant promotion by DFA through emails, fundraisers, and speeches throughout the 2004 elections.

They came from across the U.S. and ran for widely varying positions, from county sheriff to U.S. Senator. No incumbents were chosen, and members of Dean Dozens were targeted to key districts. The first list of Dean Dozen candidates included a little-known State Senator from Illinois named Barack Obama in his first race for U.S. Senate.