Blockchain based E-voting system can be revolution- ary in terms of security and tamper proof, transparent elections and hence empower the democracy. Blockchain E-voting is already implemented at organisational level. But at state/national level it faces challenges such as privacy, stability, latency etc. To counter them we require advanced implementation techniques from multiple disciplines. These techniques are 2-layer-solution, sharding for scalability issue, optimizing consensus algorithm and off-chain transaction for reducing latency, zero knowledge proof, using multiple protocols for user privacy etc. General architecture of blockchain is explained in details which combines election creation, voter registration, voter transaction, tallying the results and vote verification. We have discussed how integrating E-voting with blockchain document verification system can be benificial. It is complicated to implement at state, national level and need additional research and implementation to make blockchain E- voting acceptable in elections across the world. Through research and innovation we can make blockchain voting mainstream.