M&T Bank, Norstar seen as potential Midlantic bidders. (M&T Bank; Norstar Bank N.A.)

Two growth-minded banks, including one in Buffalo, are seen as potential bidders for some or all of Midlantic Corp.'s $2.5 billion-asset upstate New York operation.

Though officials of both banks decline comment, banking insiders in Buffalo and Albany say most speculation centers on two banks:

* Buffalo-based First Empire State Corp., parent of M&T Bank.

* Fleet/Norstar Financial Group of Providence, R.I. Fleet/Norstar is parent of Buffalo-based Norstar Bank N.A.

The two banking companies have been among the most active recent acquirers in New York and New England. Each could improve their franchise by acquiring some or all of Midlantic's four upstate …