The reward pool earns 2 STEEM per block, so that is 57 600 STEEM/day. A maximum of 25% of that goes to voters, but that is reduced in practice because authors vote for themselves (by default in the UI) and by the penalty for voting within the first 30 minutes. This might be slightly less than $100K now with the reduced STEEM price (though it was higher when TDV made his first post), but still reasonably close.