Gabrielle Carteris will seek the executive vice president position
He says that he doesn't want to split vote and rival has "better chance of winning"
Board member will oppose the current co-president, who was an architect of the merger
More than 300 member delegates unanimously approve re-election at labor organization's weekend convention in Seattle
On merging with SAG, figuring out new media and running a union in hard times.
Concerns expressed at national convention in Chicago; Reardon re-elected President.