Credit: Cliff Lipson, Ron Jaffe/CBS

Anthony E. Zuiker may argue otherwise, but the CSI franchise can’t go on forever — which is why rumors persist that at least one of the series could meet its maker by May 16, when CBS presents its fall 2012 lineup to advertisers. Common sense would dictate that CSI the mother ship should go first: It’s been on their air since 2000 and has lost three major players (Gary Dourdan, William Petersen, Marg Helgenberger) in the last decade. (We’d mention Laurence Fishburne, too, but honestly … do you miss him that much as Langston?)

But the long-running procedural has recaptured some mojo with the addition of Ted Danson as D.B. Russell and Elisabeth Shue as Julie Finlay, so it’s highly likely that CSI — as the first one in — will be the last one out.

That leaves CSI: Miami, which bowed in 2002, and CSI: New York, which began its run two years later. We’ll discuss their ratings later, but first let’s address why one of these shows may be on the proverbial chopping block: Lack of shelf space. Having already picked up 19 of its returning shows, CBS doesn’t have much room left for some of its new dramas and comedies in the works for fall — many of which sound promising. (I’m liking the sound of Baby Big Shot about a working class female lawyer from The West Wing’s Kevin Falls; a modern-day take on the cases of Sherlock Holmes that will star Jonny Lee Miller; or the period piece about a Vegas lawdog starring Dennis Quaid and Michael Chiklis).

To make room for such high-class projects, yanking Miami or NY looks like the most obvious solution; both are long in the tooth and continue to move under the radar. (When was the last time you talked about David Caruso’s grimace in the lunch room?). And though they would certainly rank as major hits on ABC or NBC, ratings for either procedural don’t come close to what CSI is earning on Wednesdays (12.5 million viewers, a 2.3 rating/9 share in adults 18-49). Miami averages 10.8 million, a 2.5/7 in 18-49 and a 3.4/8 in 25-54, while NY lures 10.5 million, a 1.9/6 in 18-49 and a 2.7/7 in the older demo.

So Gary Sinise and Co. should go first, right?

Not necessarily: The series picked up some heat by adding the beloved Sela Ward, and it’s not nearly as pricey as its counterpart. (Caruso doesn’t come cheap these days). So Miami may be the more obvious choice. Unfortunately, CBS isn’t giving any hints these days, but insiders expect talks to continue well into the next week. An answer may not be available until the eve of the network’s upfront in New York.

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