As long as it absorbed the yolk it has a chance. Had one a couple months ago with similar blood loss who lived. I held to apply light pressure with a moist towel to get the bleeding stopped.
Give water asap. I usually wait to give water until their second day because they don't really need it, but due to blood loss they are dehydrated so give immediately. I use a medicine dropper that came with my kids prescription. If you have save a chick add that to the water, if not dissolve some sugar into the water.
If it survives the night apply neosporin to the bellybutton area tomorrow and keep doing it for the next week. If loss of blood doesn't get him right away, infection might in a week or 2 so keep applying neosporin.
Good luck to you!