Story highlights Defeat in a district they've owned for a generation will put fear into Republicans

This contest -- the most expensive in congressional history -- has real meaning for both parties

(CNN) By the time Americans wake up Wednesday, there will in all likelihood be a new representative-elect en route from Georgia's sixth Congressional District to Washington. What that person does upon arrival is pretty much beside the point. It's the letter "R" or "D" next to his or her name that's become a national political fixation.

Both Jon Ossoff, the Democrat, and Karen Handel, the Republican, are party people. Despite taking steps to distance themselves from their would-be future colleagues, neither figure to turn up on Capitol Hill and make much of a stir. The winner of Tuesday's special election will be granted a relatively brief lease on the seat, about 18 months, most of them unfolding in the muck of yet another campaign season.

And still, this contest -- the most expensive in congressional history -- has very real meaning to both parties. It is, and has been for months, the foremost contest of the Donald Trump era and the first that Democrats and Republicans seem to agree should be taken as a referendum on the White House and a bellwether for what's to come in the 2018 midterm elections.

So there are lessons to be learned. Both sides are eager to begin sorting, shaping and spinning them, and then arguing with one another and amongst themselves over how those lessons should influence future tactics. Wednesday morning is not an end -- it's just another beginning.

Defeat in a district they've owned for a generation will put fear into Republicans who even a few months ago considered their seats safe from any meaningful challenge. Will it create a panic, though, with nervy incumbents flouting leadership in an effort to save their own hides? That still seems a ways off.

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