Yes, and so was Bob Menendez and George Allen was a lock for reelection
The prospect of Bob Menendez losing was never at any point more than an outside chance, even for the few polls where Kean Jr. was leading. Coleman, on the other hand, will face a strong Dem challenger b/c many MN Dems are still salivating over Klobuchar's blowout win. Your analogy dosen't work b/c:
Bob Menendez was a Dem in a blue state that John Kerry won and Bush had terrible approval ratings.
Coleman is a Republican in a blue state that John Kerry won and where the incumbent republican governor was just barely reelected, where an open Senate seat was just won by the Democrat by a 20-point margin, the Democrats increased their numbers in both houses of the state legislature, and President Bush has a dismal approval rating.
It also dosen't make sense to compare Coleman to Allen. Allen never looked truly vulnerable until the Macaca moment, while Coleman has looked vulnerale ever since Election Night '06 (maybe even before then) due to the fact that he is a fairly conservative Senator representing a blue state that seems to be trending Democratic again.
With all due respect, you seemed to misinterpret my analogy which was it is way to early to make definitive statements