Yes, it's quite easy if you have mograph. Just create the text with the mograph text object, set the letter rotation to -90 in the letter>tranform tab, and then assign a plain effector (happens automatically if the text object is selected when you create the effector), set the parameters to rotation>H = 90, and then set the falloff to linear. Animate the effector to accomplish the rotation.
Sample file:
4289_textrotation.c4d.zip