Roll Call thinks it’s a done deal, which can only mean that the Libertarians finally gave her a hard no about being the party’s nominee. Amazing. They had a chance to get a flawed candidate elected to the U.S. Senate, and instead they stood on principle with a purer nominee knowing that it meant certain defeat. Foolish or admirable (or both)? Reminds me … of Delaware.

Sen. Lisa Murkowski is strongly considering mounting a November write-in campaign to keep her seat and could make an announcement as soon as tomorrow, according to a source with knowledge of the situation…

Should Murkowski pull the trigger on a write-in campaign, GOP sources say she would face opposition from the National Republican Senatorial Committee. The NRSC endorsed Joe Miller immediately after Murkowski conceded the primary, and the GOP committee intends to stick with the Fairbanks attorney and provide him with the full weight of its backing…

While waging a write-in campaign is a daunting proposition for any candidate, the one source noted that with Murkowski’s strong name identification, fundraising ability and the state’s election laws, she could pull it off.

Serious question: Is this outcome actually better for the Democrat McAdams than having Murkowski on the ballot as the Libertarian nominee? Remember, according to that PPP poll from last month, if she ran as a Lib she’d pull 38 percent of the independent vote, 32 percent of the Republican vote, and 28 percent of the Democratic vote — a remarkably balanced haul. As a write-in candidate, though, my hunch is that those numbers will skew more heavily towards the Republican side since only the most devoted Murkowski supporters will take the time to pencil her in. And, let’s face it, the most devoted Murky fans are likely to be centrist Republicans, not Dems. Not only that, but surely some Democratic voters sympathetic to Murkowski will recognize their strategic opportunity here: If they rally behind McAdams, she and Miller will split the GOP and suddenly their long-shot nominee has a real chance at winning. So, just spitballing, what will the partisan breakdown be for a Murky write-in candidacy? Maybe 30 percent indie, 25 percent GOP, and 15 percent Democratic? If so, that’s a 10-point gap between Republicans and Dems whereas having her on the ballot as a Libertarian is merely a four-point gap. Might not be enough to put McAdams over the top but it certainly improves his chances. Or does it? What am I missing here?