"That person won't be me" sounds unequivocal to me. Compare this to Lipponen's response (translated from Swedish, Hufvudstadsbladet Oct 2009):

"There aren't even any positions to appoint yet, so I'm certainly not going to announce any candidacy here and now, Lipponen said yesterday."

Which sounds like an all-but-announcement to me, but at the very least it's not an outright rejection of the idea.

(In the interest of full disclosure, I'm not currently supporting anyone in particular for the job)

"The basis of optimism is sheer terror" - Oscar Wilde