Your LakeCountyEye regards this open display of vacillation not so much as Mark Kirk being in touch with his inner Hamlet, but instead as Mark Kirk playing a game of political chicken with the Republican party state leadership.
To be the Republican Senate nominee, Kirk needs to first win the Republican primary. It's no secret that many Republican primary voters take their guns, gays and abortion with them into the voting booth. And Kirk knows they're not likely to vote for a socially-left-of-center and gun-hating, gay-loving, abortion-tolerating candidate like himself.
So he's been waiting for concessions and guarantees from party leaders including Andy McKenna. Essentially he's waiting for his get-out-of-the-primary-free card. The only response he's gotten from Springfield so far has been the sound of crickets. Kirk arguably would be the GOP's strongest Senate candidate. The fact that the Illinois Republican party is unwilling or unable to guarantee him a primary win points to their continuing state of disarray.
Your LakeCountyEye can now go out on a limb and predict that Mark Kirk intends to stand firm and run for re-election to the 10th Congressional District. Kirk is already preparing the field by vetting his forthcoming decision in his unofficial blog, TeamAmerica10th.
In a post called Join TA's Kirk Campaign Advisory Committee, you're invited to advise Kirk on what to do. There are already a half dozen similarly-worded anonymous comments that urge Kirk to forego the Senate and stay put.
This may all be a clever head-fake on Team-Kirk's part. But your LakeCountyEye thinks that not to be.