Deleting a question now triggers an automated reputation recalc - so the if a post gets deleted; the votes are removed and your reputation should recalc and restore automatically.
You can also run a manual reputation recalc on your own account.
Go to the bottom of the page. Compare the rep you have now and the rep the report says you will have when you run the recalculation.
Click Trigger Reputation Recalc when you're ready.
This will restore all your rep from downvotes on deleted answers. It will also remove any rep you had on answers or questions that have also been deleted.