They may have lost their party's primary to Tea Party upstarts but Alaska Sen. Lisa Murkowski and Delaware Rep. Mike Castle are each making it harder for their vanquishers to win in November – by taking opposing actions.

In Alaska, Murkowski has decided to launch a write-in bid in order to retain her Senate seat. As she was weighing a decision on an expensive and uncertain write-in effort, Murkowski pointed to the smaller subset of Republican primary voters who chose upstart Joe Miller over her as outliers in the state. "When you think about the outcome of that, in a closed Republican primary, how many Alaskans were actually able to weigh in? So what is the will of the constituency? When you hear this outpouring of support and concern -- concern about the future of the state of Alaska and our representation here in the Senate -- you do feel a responsibility," she told the Anchorage Daily News.

Certainly, as an incumbent senator and the daughter of Frank Murkowski, a longtime senator and former governor himself, Murkowski's new campaign could pull significant support in November. And a recent survey of the race suggest she's got a shot to win despite the hurdles of a write-in effort.

When Tea Party favorite Christine O'Donnell shocked Castle in Delaware's Republican senate primary, a similar write-in effort appeared as though it could work as well as the one Murkowski decided on. Castle served two terms as governor of the state and has served in the House since 1992. His name recognition alone would have been a powerful argument in favor of following that path.

But Castle decided not to, saying in a statement, "While I would have been honored to represent Delaware in the U.S. Senate, I do not believe that seeking office in this manner is in the best interest of all Delawareans."

It's worth noting that a vigorously waged write-in bid by Castle likely would have drained votes from Democrat Chris Coons, not O'Donnell. Castle was viewed as a heavy favorite for the seat had he made it to the general election, after all.

The two states certainly lean in different direction – Alaska to the right and Delaware to the left. For that reason, Miller remains in position to win in, though if he does not it will almost certainly be because of Murkowski's efforts. O'Donnell remains a big underdog in, but had the moderate Castle stayed in the fray, her chances may have improved somewhat.

Murkowski calls it "will of the constituency," Castle frames it as what is in "the best interest" of his state. By taking different roads, both defeated incumbents are getting making the path to the senate more difficult for the insurgents who took them down.