Lots of shows still on bubble

With less than a month to go before the broadcast networks announce their fall schedules, fewer shows than usual have reason to worry.

ABC, CBS, Fox, NBC and the CW have already renewed a total of 26 series, ranging from old favorites ("The Simpsons," "Two and a Half Men") to newcomers ("Modern Family," "The Vampire Diaries").

Other shows got the bad news early and officially. ABC even pulled the plug on "Ugly Betty" in time for a series finale.

But a lot of shows still remain "on the bubble" — a term, drawn from a carpenter's level, meaning that the network decision could go either way.

While casts and producers sweat out the wait and viewers launch "save our show" campaigns, the people with the power are playing a big game of schedule Scrabble.

This time of year, network programmers are looking at pilots they've ordered and considering their options. What spots on the schedule are open and which shows should get them? Should a long-running series with OK ratings but increasing production costs be sacrificed in favor of a new entry, cheaper but risky? How do current shows that might have disappointing ratings but established audiences measure up against potential newcomers that might break out as hits?

NBC and Fox announce their fall schedules on May 17, followed by ABC May 18, CBS May 19 and the CW May 20.

* NBC has the biggest needs for next fall, after turning 9 p.m. weeknights over to the now-canceled "Jay Leno Show" this season. This could be good news for current NBC shows such as "Parenthood." But NBC also developed more new shows than any other network, which should give its schedulers the most options.

* CBS, on the other hand, has such a strong and stable lineup that average ratings might not be enough to save a show such as "Numb3rs," widely expected to be canceled. CBS may also feel confident enough to cut loose a show such as the increasingly expensive "Cold Case."

* ABC scored big with comedies this season and had a hit with the lighthearted procedural "Castle." This could make the network less eager to bring back such ambitious but dark shows as "FlashForward" and "V."

* Fox can't seem to create a successful live-action sitcom and finally gave up on Joss Whedon's "Dollhouse." Will the network's future look more like wry "Lie to Me" or comic-bookish "Human Target" — or neither?

* The CW's one big question mark is the one show that feels like a legacy from the old WB days: "Life Unexpected." The sweet drama reached a turning point recently in an episode that fans hope won't be the series finale.

And any look at "on the bubble" shows can't omit NBC's "Chuck." Last season, fans' passion and Subway's sandwiches saved the low-rated spy dramedy.

This spring, "Chuck" is in danger again, and its fate will depend on what else NBC likes and how much audience loyalty turns out to count. In other words, the decision on "Chuck" could go either way.