Hi,
It is 100% possible with the MQTT protocol. Actually this protocol is meant for this type of applications. MQTT has a client/server model, where every sensor is a client and connects to a server, known as a broker, over TCP.
MQTT is message oriented. Every message is a discrete chunk of data, opaque to the broker.
Raspberrry Pi is also the perfect platform for implementation. You can find and read many articles related this. all the best.