Let's play "Guess Who Was Unwilling to Say He Wants to Run for Senate?", from yesterday's New York Times:
While it might be wishful thinking, Ms. Giffords’s noncampaign is already having a major effect on Arizona politics; other prospective Democratic candidates say they feel compelled not to jump in unless she bows out, allowing Republicans to get a head start organizing their campaigns.
“I’m in but only if she’s not,” said one prospective Democratic candidate, who spoke of his deliberations but insisted that he not be named given the fluid nature of the race. “A Democrat running against her would be doomed.”
Hint: It's not Don Bivens or Fred DuVall, who both openly mentioned they would be willing to run. It feels like it should be so clear who this particular man is, but I've got nothing so far.