I wish you well with it Alexa. I looked at your with interest because you are running it and it is genre targeted.
I advise all my readers when they sign up that they are signing up to get a free book then, and a mid-monthly newsletter, and I don't feel that I can send two newsletters a month to readers who I've promised that I'd only send one newsletter a month to.
I do have 3,000 Facebook page followers (pages and private profile combined) and 2,600 Twitter followers, and I can mention your promotion in the historical fiction blog (created for the mid-month author cross-promotions) which gets between 2,500 and 3,000 readers a week. If it were acceptable to just share with those social media outlets, I'd join you for this promotion. I don't want to wear my newsletter readers out when I've been building those lists for the benefit of other authors.