Not sure about the original key, but I play it in E.

E (022100@1)        C#m (x13321@4)BHow (x2444x@1)many fantasies
Were interrupted by
A hundred galaxies
That were drifting by

A (x02220@1)              C#m (x13321@4)     BThe (x2444x@1)Mona Lisa's got you in awe
The Mona Lisa's got you in awe
The Mona Lisa's got you in awe
The Mona Lisa's got you in awe

E (022100@1)        C#m (x13321@4)BHow (x2444x@1)many apologies
Were interrupted by
Learning how to read
Looking at the sky

A (x02220@1)              C#m (x13321@4)     BThe (x2444x@1)Mona Lisa's got you in awe
The Mona Lisa's got you in awe
The Mona Lisa's got you in awe
The Mona Lisa's got you in awe

C#m (x13321@4)            EYour (022100@1)baby's sleeping, sleeping
Your baby's sleeping, sleeping
Your baby's sleeping, sleeping
Your baby's sleeping, sleeping
Sleeping, sleeping
Sleeping, sleeping...

Your baby's sleeping, sleeping
Your baby's sleeping, sleeping
Your baby's sleeping, sleeping
Sleeping, sleeping
Sleeping, sleeping...

E (022100@1)        C#m (x13321@4)BHow (x2444x@1)many fantasies
Were interrupted by
A thousand galaxies
Drifting slowing by

A (x02220@1)              C#m (x13321@4)     BThe (x2444x@1)Mona Lisa's got you in awe
The Mona Lisa's got you in awe
The Mona Lisa's got you in awe
The Mona Lisa's got you in awe