He also thanked Responsible New York for its endorsement, as well as all of his supporters.
He added that bipartisanship and cooperation is pivotal after the 2008 elections.
"All of upstate New York's elected officials are going to have to come together in a new, bipartisan coalition to balance the shift in power that we have witnessed today. That we do so is critical to the safety and prosperity, indeed the future, of our communities," O'Neill said in the written statement.
He added that he plans to challenge McEneny again in the next election for the 104th Assembly District.