i notice the tx was "relayed by ip" 76.10.140.37 . is it most likely that the transaction physically originated in/near the area that this ip resides?
Very unlikely.
When you creates a tx, your wallet broadcasts it to your peers, and your peers further relay it to the whole bitcoin network.
Eventually, somebody will relay the tx to blockchain.info and then the site will record the IP of that body.
Indeed, if you check the homepage on blockchain.info, you will find that the site is connected to "only" a few hundred nodes at a time.
https://blockchain.info/connected-nodesOr, you could push your tx directly on site like blochachian.info.
https://blockchain.info/pushtx