I agree with Judge Watford's opinion -- this isn't even a close call, so the district court was correct to deny Mr. Kennedy's request for a preliminary injunction. Judge Bennett concurs, and thinks the issue is closer than Judge Watford does. But I'm someone who's generally worried about even informal governmental coercion of free speech, and even I see the stark distinction here between, say, a letter from a prosecutor threatening arrest if a store doesn't stop selling a particular book and, here, a letter from a single senator expressing her opinion about a public issue.
Other cases might be close. This one isn't.