As @CreatureCuddler says it is a high season, expensive to travel, more sits than hosts, and also many sitters will prefer to be with their family at that time.
I agree that optimizing your sit is important and you can get help here with feedback should you want it.
Publishing dates is the best way as invitations rarely work. However, for Thanksgiving there might be people that either want to go to your area OR locals that get guests and would like to housesit so that their guests can use their home. If you choose to send invitations, be sure to only send invites to profiles you have read and want as a sitter based on that (of course you can screen also with a videocall, but don’t invite if it is clear you don’t want them) and show in your invitation that you have read their profile. (The invitations I get are usually clearly mass-distributed and not tempting to accept.)
Best of luck - there is still time and you can get help here. Here is how you add your listing to your forum profile: