In some ways I think the spanish government would prefer to stay in the euro because to come out of it would show that the spanish economy is weak and of course it may be difficult to withdraw in an orderly fashion. It would also be a double edged sword. A devaluation would stimulate its exports but expose it to higher costs of imports particularly oil.
However, it is clear that the powers that be are managing the euro based on a german economic model, which is a one fit for all members. A rising euro on the back of an increase in interest rates is the last thing Spain needs when its GDP is falling and unemployment is rising.