Immediately after the election Californians were flooding social networks with #Calexit, or their form of Brexit. Some of them were joking, upset at the 2016 election results, others very serious. Among those who was serious, Californian Governor Jerry Brown.
Immediately after the election, the Democratic governor was silent regarding California seceding from the union. The overall movement itself had not gained shape, some wanted to form their own nation, some wanted to join Canada, others wanted to take more of the West coast with them.
As the movement gained traction and turned into a possibility it seemed the only person left to join the fight was California's governor. With Hillary Clinton winning 6,965,208 votes in the election it was clear what the majority of California wanted. Brown spent some time in Canada meeting with Canadian Prime Minister Justin Trudeau during the end of November and early December. He announced that they would be "looking into every possible option and working with Canada to do what 'the people' want".
So, it looks like Californian's might get their wish and bring the number of US states down to 49. For more on how a secession from the Union could work, see this article.