Yes, you can - TurboTax automatically saves your progress but its best to make sure you Save and Sign Out. And, remember the account user ID that you used to begin your return so you can log into the correct account when you come back.
Also, the IRS is not actually processing any returns until January 29th this year (they needed extra time to prepare for any new tax law changes due to tax reform), so there is no rush to finish right now.