The traditional approach is you go relatively conservative (small c) first term, then go bolder in the second. Didn't really happen with Blair, mind - his second term's a lost opportunity.
If you can get to a point where you can say look how we've managed the economy, now we can be a bit more progressive and you can trust us to do it properly and it sounds convincing, then you might well be able to pull it off.
And *surely* they have to try and fix health and education, and it's not unreasonable to suggest that needs more than one term to do properly. The main thing is I get more depressed about how self-centred people seem to be nowadays (am hoping it's just an age vs perception thing!) and as long as they're not sick or need anything, then it's I'm alright Jack nowadays so who cares if it all goes to shit!