California leaving the Union has little to no chance of happening. The state is one of the most liberal in the entire country, and it isn't surprising that many residents want to leave the United States after Trump was elected. While many are calling for California to secede, there is a process for it to happen, with a two-thirds approval majority needed from both the House and the Senate. If you remember, Texas also called for secession during President Obama's re-election but nothing came of it.