Their Facebook page for the “Beautiful and Bald Barbie” campaign had won about 50,000 fans by Thursday — more “likes” than Mattel’s corporate page. New Jersey photographer Jane Bingham helped kick it off in December after reading about a 4-year-old Long Island girl who received a one-of-a-kind hairless Barbie from Mattel. Bingham, 41, lost her own hair while fighting non-Hodgkin’s lymphoma last year and noticed her 9-year-old, Belleliana,…