If you are like me then as soon as you receive your new phone you are already itching to root it. This is what I love about a Nexus device. You can root it right out of the box pretty easily unlike with OEM skinned devices that often take months to receive a root method. Yesterday developer "Chainfire" released CF-Auto-Root for the Nexus 6. This allows you to root your device without replacing the stock recovery. You do have to be bootloader unlocked however. Simply download the root file for your device from the link below, and then double click the root-windows.bat file to launch the rooting script.
Via CF-Auto-Root