alias scpresume="rsync --partial --progress --rsh=ssh"
This command uses rsync, and sets options for resumable transfers (--partial), displaying a progress bar (--progress), and insures that the transfer will be made using secure shell (-rsh=ssh). To use the command, open a new shell after saving your modified .profile file, and then type scpresume in place of scp in your normal transfer command.
[robg adds: I added detail to the original hint submission, so I apologize if I got some of the details on the rsync options incorrect.]

