America is rallying around Jay Leno-or at least that’s what NBC wants America to think. In the network’s new $1 million ad campaign, ”America Stands Up for Jay,” average citizens proclaim their undying, don’t-touch-that-dial devotion to Johnny Carson’s heir. Awash in the same small-town patriotic glow as Ronald Reagan’s ”Morning in America” campaign ads, the promos are debuting just as Leno celebrates his first anniversary as host of The Tonight Show. ”Creatively, we think The Tonight Show is in great shape,” maintains NBC president Warren Littlefield. ”The campaign is just saying ‘We have our act together.”’ Yet the fact that NBC must spend a million bucks to remind us all of how much we love Jay is indicative of the problems that have confronted Leno over the last year. First there was the appearance of feuds with the lower-rated Arsenio Hall. That was followed by the forced ouster, in September 1992, of his thorny longtime manager (and the show’s executive producer), Helen Kushnick, with whom Leno says he now has ”no relationship.” Then, last winter, Leno could only watch as NBC publicly dangled his job in front of David Letterman, who spurned it to accept CBS’ $42 million offer. Finally, TV critics and audiences alike have charged that the once bitingly sarcastic Leno has transformed himself into a toothless, ultra-bland Mr. Nice Guy. At no time has that accusation seemed more deserved than during the result of the ill-fated decision to celebrate Cheers’ final episode by broadcasting the entire Tonight Show live from Boston’s Bull & Finch pub. Leno ineptly struggled to maintain cheery control over the telecast as the inebriated cast of Cheers started a spitball fight on national television. Washington Post television critic Tom Shales called the outing ”an appalling shambles.” ”We walked in on a drunken party,” concedes Leno. ”I’m not putting them (the cast) down. I’m grateful they agreed to appear. And ratings-wise, the show did well. But was it a great show? No.” In fact, even though the program was an embarrassment, its ratings were the third-highest in Tonight’s 39-year history (behind No. 1, the 1969 marriage of Tiny Tim and Miss Vicky, and Johnny’s May 1992 farewell). Moreover, after a rocky start, The Tonight Show does appear to be back on track. Even without the Cheers special, Leno would have won the May sweeps ratings period, crucial for network prestige and ad rates. Bandleader Branford Marsalis, who has been criticized for looking uncomfortable on camera, is cracking the occasional smile. Most important, Leno is adored by the network’s much-valued affiliates. ”The affiliates have stood up for Jay, and with the numbers the show’s been getting, it’s clear America, figuratively, is standing up for him too,” says John Miller, NBC’s executive vice president for advertising, promotion, and event programming. But however many are standing up for Jay now, Leno and NBC are all too aware that in two months they’ll be facing new, formidable competition for the public’s affections when Letterman’s show enters the 11:30 p.m. time slot, already crowded by Leno, Ted Koppel, and, in many markets, Arsenio Hall. (They’re less worried about Chevy Chase’s 11 p.m. talk show, which begins Sept. 7 on Fox.) The ad community is keeping a close eye on the looming late- night race-and the ”Stand Up for Jay” campaign, too. ”NBC’s Jay Leno is a brand, so (this campaign) is a test of brand loyalty to see how he’s doing before the audience is faced with a lot more brands on the shelves,” says Betsy Frank, a senior vice president at ad agency Saatchi & Saatchi. The star admits he hasn’t been entirely comfortable taking over for Carson, or with all the attendant scrutiny. But Leno, who often speaks in the editorial we, says, ”We’ve now proven we can do the job, thank you. We do the best monologues. The show is getting stronger. Branford is getting looser. There are people who like you and people who don’t. There’s nothing I can do about that.” Not that NBC isn’t trying.