During the mortgage application process your loan officer requests what's called a Verification of Deposit from your bank and submits it to the lending institution. Once the loan is ready to fund, the lender will call the banking institution to once again verify that you haven't depleted the funds in your account per the verification of deposit.
So the answer to you question is "Yes." You can be denied for a loan if your reserves fall short of what the lender is asking.
In this instance, you might want to ask a friend or family member to lend you the funds until after the loan funds.