No, people who think that congressional elections are more national than local are fools.
Most voters do not confuse their local congressman or senator with Bush. Most voters cast their vote for the person and not the party affiliation.
Some times presidents have coattails that influence a little bit.
Example: Nixon did not bring down the Republican party. With the (short) exception of Carter's presidency, the party rose to new heights.
You remind me of some passengers I've had offshore: "Oh my God...a wave...we're all gonna die!"
The Sixth Year Swoon gonna get you.