If I win $40,000.00 tax free in a Michigan Lottery on April 15,2013 (income tax deadline) what is the real win?

I make about $40,000 dollars (between Social Security and a Ford Motor Pension) and I wonder if I won $40,000 tax free what the real amount of the winning would be?
makes me wonder
Update: The deal with the Michigan lottery is the state bills me and the lottery makes up the difference
why would I pay anything if the state pays my tax?
this is kind of confusing
where do you get the 15% tax?
Update 2: Thanks anyway ROB
do we now ROB Peter to pay Paul?
my name is Paul ~by the way
how do this thing work?
Update 3: WOW! THREE TOP CONTRIBUTORS
I guess its that I BELIEVE THE state of Michigan
when they say I will win this$40 grand tax free
maybe in the end the Federal Gov't and social security will get their 30 pieces of silver
Update 4: the state of Michigan has a TAX FREE
The$40,000.00 top prize is NET of STATE and FEDERAL TAXES on the gross

so many people answered that I MUST
pay a tax..this tax information is advertixed for the March 15, 2013 drawing~the day the income taxes are due
FYI
5 answers 5