Before 2008, the last race that went far beyond Election Day was in 1996, when Sen. Mary Landrieu (D-La.) narrowly defeated Woody Jenkins (R). The state certified the election results, but Jenkins challenged them, claiming "widespread vote tampering." Though the case was still pending when the next Senate convened, Landrieu was seated "without prejudice." But in that case, there was precedent of the Senate recognizing a senator if the election has been certified by the state, and in Alaska the results won't be certified until the court proceedings wrap up.
The previous contested Senate results were back in 1974, when Sen. Henry Bellmon's (R-Okla.) victory over Rep. Edmond Edmondson (D) was challenged. In this case, too, the election had been certified despite a challenge, and the Senate seated Bellmon without prejudice. While the history of contested elections is long and colorful -- in a contested West Virginia Senate race in 1946 there were allegations of a precinct in which drunken polling officials intimidated voters with firearms -- Senate Historian Don Ritchie couldn't think of any instance of a senator losing seniority due to a drawn out election challenge.
"I don't see anything exactly parallel to that," said Ritchie. "There's a certain degree of collegiality that's maintained."
And while there's no precedent in Senate history of a senator losing their seniority for these reasons, there is precedent in this campaign of the Senate Republican Conference acting collegially toward Murkowski. After Murkowski lost the primary and re-entered the race as a write-in candidate, the Senate GOP caucus voted to allow Murkowski to retain her committee assignments. It seems likely, if this lawsuit drags on to January, that the conference would act in a similar manner again.