The Mazda's rotary gets ~70-75HP if the internet is to be believed. But oh, unlike many PHEVs that have 30-ish miles of range it has 50, so it's got a decently larger battery and starts to get into the 'Where GP is right about plug-in hybrids being marketing fluff'.

My general understanding is that they are a very unpleasant experience in such a state despite whatever range advantages you are given. Because of the relative weight of the batteries to give even 100 miles of range, the small engine isn't that useful on the highway and on a steep hill even less so.