TONAWANDA, New York-Martin Kober is convinced the painting of a dying Jesus that hung above the mantel in his childhood home is the work of Michelangelo. Getting experts to agree remains the $300 million hurdle.

That's the potential value of the 48-by-64-centimeter work that Kober's family affectionately calls "The Mike", a one-time living room fixture that occasionally got dinged by a thrown tennis ball and once fell from the wall while being dusted.

Kober has for the last 15 years taken his Michelangelo suspicions to the art world and gotten a mixed bag of scholarly opinions. For now, the circa 1545 family heirloom that was given to Kober's great-great-grandfather's sister-in-law by a German baroness remains in an out-of-state vault while he seeks the elusive validation.