[SLCN.CautioN]

Hey, Yeah it is possible to do a bunker rush against a toss. '1 gate expand / forge expand'
If the toss went one gate expand you can bring 3-4 scvs 'depending on what makes you feel comfortable' and 4 marines. When you reach his expand quickly put down two bunkers then a third bunker right 'At this time you are probably being attacked by a defending zealot so make sure you micro marines back whilst shooting at the zealot'. One bunkers are done hop inside and shoot shoot shoot!!! Just keep rallying marines to the bunker and win .

Forge expand
If he forge expands you can bring the same amount of units 3 scvs this time and walk around the natural depending on the geographics of the map. build a bunker behind or in his mineral line depending on the cannon position/timing and build another right beside it.
To drag on after that, once you kill his nexus you can salvage your bunkers and bring back whatever remains and leave one bunker with one marine in it to keep scout of his '2nd' expand time.