Dear Miss Snark:
What if, after landing an agent (but before landing a publisher), a novelist hired a publicist to get publicity for a book, pre-sale. Yes, bass-ackwards you would say. But say the book involved current issues and a premise that drops jaws. (The Secret Lives of Dentists perhaps?)
Assume the writing ain't never gonna win no Pulitzer Prize, but has been edited by a freelance editor who's name all publishers will recognize. (all. ya, right)
Now say that the publicist actually managed to get some press for this (yet unsold) novel. Not NYT, but solid bites from a variety of regional newspapers. Is that the sort of thing that would help convince publishers that the book might actually sell?
What kind of press do you think you can get for an unsold novel? What you're describing here is getting press attention for a current issue. Unless your "jaw dropping premise" book is about orthodontia, I assure you that your sense of what's gonna get press attention and what IS gonna get press attention are two entirely different things.
Do you think editors read regional papers? Miss Snark may know the lovely folks at the PI; the Freep; the Rampage, and various incarnations of The Trib - not to mention the hunky guys at Cattle Today; that doesn't mean anyone else in the 212 does. And "read this feature/news/filler item, it's jaw dropping, in Cattle Today" is NOT a persuasive pitch for a novel. Not now, not ever.
Remember, novels take a year or more to be published. What's on everyone's hot list today is old news tomorrow.
Publicists START at $10,000. You're going to spend that before you have anything to sell? Yes, you are the nitwit of the day.
Clue: Write well. That's all.