FACTBOX-Picking the bones out of the Spanish power sector

By Joe Ortiz and Carlos Ruano

March 14 (Reuters) - There is market speculation of all sorts of possible tie-ups in the Spanish energy sector following the victory of the ruling Socialist Party in Spain's election last Sunday.

The Socialists did not win an absolute majority so will need agreements with regional parties to govern, which could have an influence on the outcome of the expected energy sector shake-up.

Analysts agree that any hostile move on Iberdrola (IBE.MC: Quote, Profile, Research) would almost certainly have to be in cash at a time when credit is tight in the markets.

Following is a breakdown of the parties involved, merger options and probability ratings given by analysts at Exane BNP Paribas this week.

IBERDROLA, GAS NATURAL (GAS.MC: Quote, Profile, Research) AGREE A MERGER

Would create Spain's biggest power company with assets from upstream gas production to household sales.

Would keep nationalist politicians happy and create Spanish energy champion.