You can install the plugin of beesu for gEdit, using YUM. What you have to do, is to open a new terminal and type:
$ su -
# yum install gedit-beesu-plugin
It's possible to install this plugin everywhere, in all GNU/Linux distributions, downloading the source code of this plugin and following the installation manual!! From the source code it's possible to configure the gedit-beesu-plugin to use gksu or gksudo as GUIs for su, whereas in some environments beesu could be not available!
When you've got gedit-beesu-plugin installed, you've to activate it for your user:
Dialog window at: Edit -> Preferences -> Plugins -> [X] Open as root
You'll have a new menu item in the Tools menu: