SQL update w/ multiple parameters

What is wrong with the following update statement. I receive the following error: Syntax error in UPDATE statement.

UserSession.adoCmd.CommandText := 'UPDATE Project_Setup1 SET [Contract_Number, ' +
'Contract_Type, Award_Date, Start_Date, Estimated_Completion_Date, Task_Order_Number, '+
'OpNum, Site_City, Site_State, Site_Zip] = :Contract_Number, :Contract_Type, ' +
':Award_Date, :Start_Date, :Estimated_Completion_Date, :Task_Order_Number, ' +
':OpNum, :Site_City, :Site_State, :Site_Zip WHERE Project_Number = :Project_Number';

Any help would be greately appreciated.

-Robert Sims

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