Yes, your certainly can. There is a flat $5 USD charge to transfer your USD into Stake.

Once you have an account, check out your Profile Page for your wire/transfer details under USD > USD Transfers.  On the app, head over to the 'Account' page and select ' Direct USD transfer' for your wire/transfer details. 

Please make sure to include the reference details as this ensures the USD end up in your name! In addition, make sure funds are being sent in your name as we are unable to accept payments from third parties.