My initial thought was that it was an ad for National, but on second viewing I realised that the so-called "Plain English" part was actually not plain English at all.

If you pay attention, and view the whole add.... no, not really.

But if you arent paying close attention, or only see the first two thirds.... then yes, it can appear to be promoting Bill English's ability to affect those changes in the economy...

And really.... how often do you sit down and pay attention to an Ad? As opposed to say, start chatting to your co-watcher, or get up and go to the loo, or put on the kettle....
Many ads are designed to convey a message thats not overtly stated, or that gets through partial inattention....

My ungrounded instinct would be that it wouldn't meet a 'promoting party' threshold for legal purposes.

But it is sort of
Bill English = Economy
Bill's Message About Economy!
Watch 7's Bill English Month!