Also, there doesn't seem to be much evidence that unpopular governors of one party have any real effect on Presidential candidates of the same party.
Personally, I don't think they do. Jon Corzine didn't hurt Obama in New Jersey, Gray Davis didn't hurt Kerry in California, Rod Blagojevich didn't seem to hurt Obama in Illinois in 2012, either (though that was like 3 years earlier). Meanwhile, Matt Blunt's very low approval ratings in 2008 didn't help Obama in Missouri, even in what was considered a bellwether state up until that point.
It's more like an unpopular president can severely hurt his party all the way downballot rather than the other way around, as we have seen with Nixon in 76' and 78' (whose terrible affect on the GOP was seen at almost every level in almost every state for years after), Bush in 2006 and Obama in 2010/2014.
This Connecticut idea is rubbish (as usual StatesPoll does not disappoint!). The GOP has lost big there ever since 1992, with progressively bigger losses over time. The best they could possibly hope to do is trim the Democratic margins down from a landslide to a comfortable win.
