Context:
The negotiations were led by the deputy chief of the provincial Communist Party committee, Zhu Mingguo, and the party secretary of the administrative region of Shanwei, Zheng Yanxiong. Mr. Zhu is a top lieutenant to the provincial party secretary, Wang Yang, one of China’s most prominent political leaders and an unspoken candidate for a spot on China’s ruling body, the standing committee of the Politburo, when membership in the body, which now has nine seats, turns over next year.
I don't think it's a common word in that sense,although it seems to be carrying that meaning here, which sounds to me like a sarcastic understatement. However, i'm not sure,, since I'm not very familiar with the Chinese political climate.The intonation of the speaker is also quite important.
This is quite a common usage in Aus/NZ English and I often see it in other contexts.
Typically:
"There are plenty of in-form players vying for a spot on the national team".
"If you impress the right people you might get a spot on the local development committee".
not a teacher
Thank you both.