It may, given that the MR18 consumes 9.8W and theoretically 19Watts are provided via PoE passthrough according to the datasheet:
http://www.downloads.netgear.com/files...
Having said that, the device itself needs to be powered via a PoE+ (802.3at) port otherwise only 7.9W will be provided to the PoE enabled ports which is probably not enough.