According to Pollstar who tracks these sorts of things, 3 EDM artists made the top 100 concert tour lists for 2012 year-to-date. These include:
Steve Aoki: $4.5 million grossed, 138,530 tickets sold
Avicii: $4.1 million grossed, 100,539 tickets sold
Bassnectar: $3.5 million grossed, 98,724 tickets sold
should we include the LFMAO tour on this list? they actually were higher than all of those with $6.5 million grossed and 151,656 tickets sold.
Important to remember: these #s are based solely on official tours so single shows for say Tiesto added together would not be listed here.