How do I keep the cron from removing a poll from my front page?
I would highly recommend Elysia Cron, it allows fine grained control of crons provided by modules (ie poll) in which you can completely disable the cron of a specific module (or change the timing from the global setting for that specific module's cron; in your case, 1 hour), which seems like something you might need to try out.  See attached for an example settings screen on a D6 site (the checked boxes mean that cron is disabled).