Sure, Lugar can't lose whereas Mourdock can. But the seat is unlikely to flip regardless, and it has not yet been proven that Donnelly is a top-tier candidate. Sure, he held on in 2010, but he was running against a complete nut.
I think that, other than Evan Bayh, Donnelly was the Democrat's best candidate.
I think there are a couple of more proven candidates than Donnelly, but I doubt they would have run, and neither would have Evan Bayh. So, we basically agree. But that does not necessarily mean Donnelly is a top-tier candidate - there is a distinction.
