Because I can't find any other reason why he hasn't thrown Norm Coleman overboard. Coleman is going to lose. Despite years of aggressive court-packing by conservatives, tempered only modestly during the Clinton era, the law is the law and an election is an election; conservatives aren't going to undo an election count just because the results don't suit their tastes (note the distinction between Bush v. Gore wherin GOP allies on the Court stopped a count that might have changed the outcome). This isn't middle school kickball; you don't get endless do-overs or partial credit for coming very very close. Appeals are only going to postpone the inevitable.
But fifty-nine Democratic Senators are not much more dangerous than fifty-eight Democratic Senators. Arlen Specter has been effectively neutered by the primary process, flip-flopping on EFCA, probably the only bill where he would have been the deciding vote. Democrats have their hands full already between Ben Nelson, Evan Bayh, and the surprisingly skittish Mark Pryor and Blanche Lincoln. Any bill that passes will almost certainly have the votes of at least two Republican Senators, meaning that Franken is in some sense superfluous. So why waste the money, except perhaps because Cornyn wants Democrats to have an easier time getting to a veto-proof majority?