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4 of 4 Golfed 2 more bytes

Pip, 22 20 18 + 1 = 19 bytes

Y_@?qMgsX(MXy)-y.g

Takes strings as command-line arguments and delimiter from STDIN (idea borrowed from Martin's CJam answer). Uses -n flag to print output values on separate lines.

                    g is list of cmdline args; s is space (implicit)
    q               Read the delimiter from stdin
 _@?                Construct a lambda function that takes a string and returns
                       the index of the delimiter in it
     Mg             Map that function to each remaining item in g
Y                   Yank the resulting list of indices into the variable y

         (MXy)-y    Take the max of y minus each element in y
       sX           Space, repeated that many times...
                .g  ... concatenated to each item in g
                    Print, newline-separated (implicit, -n flag)

And an example run:

C:\Users\dlosc> pip.py -ne Y_@?qMgsX(MXy)-y.g "Programming, Puzzles" "And, Code golf"
,
Programming, Puzzles
        And, Code golf