If you have already e-filed or mailed them then no you cannot refile them. If by any chance you e-filed and they get rejected (you will get an email confirming if they were accepted or rejected soon after you file them) then yes you can edit them and refile them but that is the Only way you can refile them if you have already submitted them to the IRS
If you need to make changes to them and they have already been accepted then you will need to file an Amendment and print and mail in the Amendment. Amendments cannot be e-filed.
If they have not yet been filed or they were rejected and you need to get back into your return after you log in, click on the State tab up top then click on Add a State ( you will not be adding a state, this is just a way to get you back into your return to make any changes you need to ) and then file your return again.
If you need further assistance or have anymore questions please let us know, we are happy to help you.