Not at this time. Our system does automatically send a number of customizable emails that contain your contest and participant information (detailed here), but we do not offer the option to send one-off emails outside of these automatic emails. We've explored the option, but it's currently cost prohibitive and would force us to raise our fees.
If you are interested in sending out a custom email blast using your own email provider, we have instructions on how to find participant email information right here:
We also have a number of email messaging examples at the following link: