Gun control advocates raised $3.6 million over the last two years to put an initiative to tighten background checks on the November ballot. Nevada requires mental health and criminal background checks for anyone buying guns from a licensed dealer. Unlicensed dealers at gun shows and others making sales don’t have to run those checks. Initiative backers say that’s a loophole giving access to guns to felons and the mentally ill. The Nevada initiative would exempt the sale or transfer of firearms between immediate family members, temporary transfers in the event of imminent death or bodily harm and temporary transfers at a shooting range, or while hunting or in the presence of the owner.