In both cases, the message submitted with spaces. Just a different number of them in the one where you used tabs.
I don't remember off the top of my head what the ASCII is for a horizontal tab, and don't know if it'd work.
Personally, I think both attempts look fine.
If you're working the text in Notepad or something like that, make sure you're using a fixed-width font in it, too, or you won't be able to see what the alignment's gonna look like.
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