* Chinese online posts show surging interest in franchise

* First Disney 'Star Wars' film opens in China on Jan. 9

* China key if Disney film to join top-grossing movies

* Early 'Star Wars' movies first shown in theatres this year

* Disney marketing blitz featured Great Wall, China pop star (Adds link to Reuters TV video)

By Adam Jourdan and Lisa Richwine

SHANGHAI/LOS ANGELES, Dec 24 (Reuters) - After a mammoth marketing campaign, growing online chatter in China around "Star Wars: The Force Awakens" suggests the latest installment of the hit franchise has a shot at breaking box office records in the world's second-largest movie market.

China is crucial if Walt Disney Co's first foray into the world of Jedi knights is to earn a spot among the top-grossing films of all time. The movie, the seventh in a near 40-year-old franchise, surged past "Jurassic World" to set a global opening weekend record of $529 million.

Disney has had to work hard for its "Star Wars" buzz in China. Though the franchise launched in 1977 - a year after the end of the Cultural Revolution and the death of China's founding leader Mao Zedong - the original films weren't shown in movie theatres until this June.

But after promotions featuring everything from 500 model stormtroopers on the Great Wall to a pop star dubbed China's answer to Justin Bieber, a Reuters analysis of posts on popular microblog Sina Weibo shows "Star Wars" has been mentioned around 700,000 times since the start of December, outpacing other big hit Hollywood releases in China this year.

"I roughly know the story plot but I have never seen any of the films in the series before," admitted Yao Yiyun, 22, a computer programming student in Shanghai. "When it comes out at the cinemas I want to see it though, especially because I like science fiction."

Online chatter won't guarantee box office success in China for the film, which has a red-carpet premiere in Shanghai on Sunday and goes on general release in the mainland on Jan. 9.

But curiosity among the world's biggest online community could help the film rival smash hits like action movie "Furious 7", the latest in a series long popular with Chinese viewers that took over $180 million in its opening weekend in China.

Over a comparable period in its pre-release schedule, "Furious 7" had racked up 230,000 Weibo hits, before soaring to over 300,000 hits in a single day when it opened this year.

Jeff Bock, senior box office analyst at Exhibitor Relations Co, predicts "The Force Awakens" will take in some $100 million during its first weekend in China. Others forecast more.