Subj:XXXX, enter for a chance to win a night at any Marriott
Assuming direct copy/paste from the email, a hover over the links show email.chase.com which is pretty reliable to tell it did originate from Chase and is not linking you anywhere suspicious. Following the links takes you to valid 1000 nights promo site or Chase/Marriott Rewards sites as expected.
Conclusion: it's real, go ahead and sign up if you haven't already.
Hi Insiders - This is a legit promotion from Marriott Rewards Credit Card. Below are some additional details:
Feel free to reach out with any questions. Good luck to those who enter!!