Yes, you can do that.
If you are using one of the CD/downloaded versions of TurboTax, there is a built-in worksheet that will allow you to make the comparison fairly easily. See the following TurboTax help article for details:
How can I compare Married Filing Jointly with Married Filing Separately?
If you are using TurboTax Online, the process would be more difficult because you would need to prepare three returns using three different TurboTax accounts. Then, you would only file the one Married Filing Joint return or the two Married Filing Separate ones.
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