A victory by the team seems 'within the realm of possibility'. [=a victory seems possible]
It's not 'beyond the realm of possibility' [=it's not impossible] that he will return.
new discoveries in the 'realm' of medicine
(..) we shall examine the human heart. It is more fragile than your own. As we pass through the flaming turmoil which is the edge of your own galaxy... ...we will enter the realm of the red Krypton sun... ...source of your strength andnourishment... ...and cause of our eventual destruction. (..)1978 Superman