The Music Reference RM-200 MkII might make for a nice amplifier choice for Maggies as @bdp24 noted. One of the reasons is that it is one of the few if not only amplifiers with a tube output stage that outputs more power into lower impedance loads. As measured by Roger Modjeski on his bench the amp puts out 112 watts into 8 ohms, 145 watts into 4 ohms, and 125 watts into 2 ohms.
Tubes and less sensitive speakers
I love the sound of tube amps but I use Maggie 3.7's. I have tried an 45 watt tube amp and while I loved the clarity of midrange, I missed the low end slam, even with a sub. Is there a tube amp out there that matches well with Magnepans? I am using the Hegel H360 and a friend recommended Coda high current amps but I still am thinking tubes.