Yes you can.
However, currently, as soon as you 'hire' a candidate, the vacancy will automatically close.
You will need to manually re-open the vacancy after each hiring.vacancy
To do this, go into to your closed vacancy:
And click 're-open vacancy':
You will need to re-set the publication dates and click 'reopen':
Please be assured that this will not affect the status of the previously hired applicant.