Andrea Riseborough got the nod for the little-seen “To Leslie.” The Academy of Motion Picture Arts and Sciences is reviewing whether her A-list campaign violated rules.When the Oscar nominations were announced last week, one of the most surprising was Andrea Riseborough’s inclusion in the best actress category.Ms. Riseborough’s portrayal of a former lottery winner battling addiction in the little-seen “To Leslie” had received scant recognition on the awards circuit. Few critics included the film on their best-of-the-year lists, and it made just $27,000 at the box office during its initial release in October.Yet just as voting for the Oscars began, a number of A-list actors started lauding Ms. Riseborough’s performance publicly. “Andrea should win every award there is and all the ones that haven’t been invented yet,” Gwyneth Paltrow wrote on Instagram, joining dozens of actors like Edward Norton and Susan Sarandon who lavished praise on Ms. Riseborough. Kate Winslet hosted a screening of the film, and during a virtual question-and-answer session with Ms. Riseborough and the film’s director, Michael Morris, called Ms. Riseborough’s work “the greatest female performance onscreen I have ever seen in my life.”“The thing that feels most exciting is being acknowledged by your community,” Ms. Riseborough told The New York Times on the day she was nominated. “It’s a marker by which we measure ourselves in so many ways — by those we aspire to be like, or those we admire. So it’s huge.”But what at first seemed like a story of how a grass-roots — though star-studded — word-of-mouth campaign had managed to help a respected actress crash the Oscar party quickly drew backlash.There were soon questions of whether the efforts on behalf of Ms. Riseborough had violated Oscar rules (“Was the Andrea Riseborough Oscar Campaign Illegal?” read a headline in the Hollywood newsletter by Puck’s Matthew Belloni) and whether Ms. Riseborough, who is white, had secured a nomination that may otherwise have gone to a Black actress like Viola Davis (“The Woman King”) or Danielle Deadwyler (“Till”).“We live in a world and work in industries that are so aggressively committed to upholding whiteness and perpetuating an unabashed misogyny towards Black women,” Chinonye Chukwu, the director of “Till,” wrote on Instagram after the nominations. Ms. Chukwu did not mention Ms. Riseborough or “To Leslie” in her post.Interviews With the Oscar NomineesMichelle Yeoh: The “Everything Everywhere All at Once” star, nominated for best actress, said she was “bursting with joy” but “a little sad” that previous Asian actresses hadn’t been recognized.Angela Bassett: The actress nearly missed the announcement because of troubles with her TV. She tuned in just in time to find out that she was nominated for her supporting role in “Black Panther: Wakanda Forever.”Andrea Riseborough: A social media campaign by some famous friends netted the star of “To Leslie” her first Oscar nomination. Here is what she said about being nominated.Ke Huy Quan: A former childhood star, the “Everything Everywhere All at Once” actor said that the news of his best supporting actor nomination was surreal.Austin Butler: In discussing his best actor nomination, the “Elvis” star said that he wished Lisa Marie Presley, who died on Jan. 12, had been able to celebrate the moment with him.The Academy of Motion Picture Arts and Sciences will take up the matter of Ms. Riseborough’s nomination during a previously scheduled meeting on Tuesday. Among the issues will be whether the campaign violated any academy rules and, if so, what the repercussions should be.At issue seems to be the efforts by the actress Mary McCormack, who is married to Mr. Morris, and her manager, Jason Weinberg, who also represents Ms. Riseborough, to get her friends and acquaintances in the entertainment industry to watch the film and talk about it. Neither Ms. McCormack nor Mr. Morris is a member of the academy, though many of the actors who praised Ms. Riseborough’s performance are.Howard Stern, Ms. McCormack’s co-star in the 1997 film “Private Parts,” praised “To Leslie” on his satellite radio show, and the veteran actress Frances Fisher repeatedly posted about it on Instagram, writing on Jan. 14 that voters should select Ms. Riseborough since “Viola, Michelle, Danielle & Cate are a lock for their outstanding work.” Mentioning competitors or their films directly is verboten when campaigning. Voters are also not supposed to be courted directly, without the academy acting as a gatekeeper of sorts.The specter of rescinding Ms. Riseborough’s nomination has been raised, but one longtime academy member, who discussed internal matters on the condition of anonymity, considered that unlikely since she did not make the direct appeals to voters herself. An acting nomination has never been rescinded, though it has happened in other categories.Ms. Riseborough declined to comment. Mr. Weinberg did not respond to requests seeking comment from him and Ms. McCormack.The academy declined to comment for this article, but it released a statement that said, “We are conducting a review of the campaign procedures around this year’s nominees, to ensure that no guidelines were violated, and to inform us whether changes to the guidelines may be needed in a new era of social media and digital communication.”Oscars campaigning has been a blood sport for decades. The modern Machiavelli for the process was, after all, Harvey Weinstein, who became notorious for bludgeoning would-be voters with parties, screenings and not-so-subtle whisper campaigns.The process has become only more sophisticated. In 2019, for instance, Netflix rented two soundstages on a historic movie lot in Hollywood to push for “Roma.” The voters who attended “‘Roma’ Experience Day” received breakfast and lunch and there were hours of panel discussions with Alfonso Cuarón, the movie’s director, and his crew.But there are rules, many of them put into place after Oscar campaigning turned into an entire industry, employing scores of consultants and strategists and generating millions of dollars of revenue for the trade publications that accept “For Your Consideration” advertisements.Studios are permitted to send out only one email a week to Oscar voters, and they cannot send them directly. The emails must be routed through messaging services sanctioned by the academy. According to one awards consultant, who described the process on the condition of anonymity, each email blast can cost $2,000.Screenings are permitted, with “reasonable” food and drink. (The rule book doesn’t spell out the definition of “reasonable.”) Everything must be provided in the same location where the movie was shown. Lavish dinners across the street or across town are not allowed.As for individual lobbying, the academy includes only a one-line explanation of what is forbidden: “Contacting academy members directly and in a manner outside of the scope of these rules to promote a film or achievement for Academy Award consideration is expressly forbidden.”In 2010, Nicolas Chartier, a producer of “The Hurt Locker,” was barred from attending the Academy Awards after he sent emails to voters urging them to vote for his film and not “Avatar.” In 2014, the composer Bruce Broughton contacted members directly, asking them to vote for his song from the unheralded film “Alone Yet Not Alone.” He received a nomination, but the academy rescinded it. In 2017, a sound mixing nomination for Greg P. Russell (“13 Hours: The Secret Soldiers of Benghazi”) was rescinded for a similar reason. In each case, the academy declined to add a fifth nominee.Ric Robertson, the academy’s former chief operating officer and a member for 24 years, said a failure to address the issues of personally lobbying voters could lead to more concerted campaigns.“This campaign sounds like it was organic,” Mr. Robertson, who was involved in putting many of the campaigning rules into effect, said of Ms. Riseborough’s situation. “It came about because a couple of prominent people really liked the film and the performance and used their connections to promote it. Well, it could get a lot more organized next year and institutionalized at other companies.”Though “To Leslie” was unknown to many voters before numerous stars began praising it, Ms. Riseborough is a respected British actress with a chameleonic flair. She has spent the past two decades playing complicated women in mostly independent films. She has worked for directors as varied as Alejandro G. Iñárritu (“Birdman”), Tom Ford (“Nocturnal Animals”) and Mike Leigh (“Happy-Go-Lucky”). Mr. Morris previously directed her in the Netflix series “Bloodline.”And since the questions about Ms. Riseborough’s campaign have arisen, there has been a backlash to the backlash. The “unabashed solicitation of Oscar votes,” The Hollywood Reporter’s Scott Feinberg said, “is a tradition almost as old as the academy itself.”For the Oscars, this is the latest in a string of controversies in recent years. Some were self-inflicted, like the two consecutive years the organization nominated only white actors, which spawned the hashtag #OscarsSoWhite and led the academy to begin overhauling and diversifying its membership. The exclusion of Ms. Davis and Ms. Deadwyler, and Ms. Chukwu’s comments after the nominations, show that the issue remains a raw one.Last year, as the Oscars were trying to recover from the pandemic, Will Smith shocked a global audience by slapping Chris Rock onstage during the telecast. Shortly after, Mr. Smith returned to the stage to accept the best actor trophy. The academy subsequently barred him from Oscar-related events, included the ceremony, for the next decade.As for “To Leslie,” which barely had the funds to pay the $20,000 fee to submit it to the academy’s portal so members could watch it, all of the attention has seemed to help, a little.Momentum Pictures, its distributor, returned the film to six theaters this past weekend, betting that Ms. Riseborough’s nomination would intrigue audiences. According to The Hollywood Reporter, it grossed around $250,000. More