Your previous grades are rough, but UCs like positive grade trends. If you can keep getting good grades and find a really compelling way to tell your story through the essay portion of the application, you have just as much of a shot as anyone.
You just need to keep getting good grades, find some ways (if possible) to be involved on campus or in the community, and submit a killer application. You can take extra (easy) classes online as a way to boost your GPA a bit as well along the way or during summer, just choose the classes wisely.