Whenever a mortgage lender pulls your credit, provided they pull what is called an RMCR (Residential Mortgage
Credit Report) then it triggers the credit repository score card (the logical computer data table used for determining your score) to not drop your score for additional inquiries within 14 days of the original credit pull. Nearly all mortgage lenders use an RMCR.
This is one of the rare instances where additional inquiries would not hurt your score but I highly suggest that you only have 1 pulled and tell the other lenders you contact what your middle score is. I would still avoid having them pull your credit if you can.
Even though your score may not be impacted it does not mean a lender may not turn you down due to your high number of inquiries.