I've heard, I have not seen the historical data, that for the majority of mid-term elections, where the executive and both houses are under the control of the same party, there is typically a marked reversal, and it doesn't matter which party is in power. So, personalizing this, if it does indeed occur, is off the mark. At any rate, it's been my sense that the country as a whole seems to do better when the executive and congress are "opposed", but that could be an accident of timing and the economy.