I think I'm getting closer to a solution. I tried starting X as follows:
startx -- - logverbose 5
Following are are last few lines of the output:
-keeptty don't detach controlling tty (for debugging only)
xinit: No such file or directory (errorno 2) unable to connect to x server
xinit: No such process (errorno 3): server error.
So now the question is how do I figure out what file it's looking for?