DENVER (AP) -- The father of Columbine victim Daniel Mauser is urging Colorado's senators to vote against a measure that would allow people with concealed-weapons permits to take their weapons across state lines.

Tom Mauser's appeal was in a full-page ad in Wednesday's Denver Post, paid for by a group called Mayors Against Illegal Guns.

The ad asks Sens. Mark Udall and Michael Bennet to vote against the measure. It says Colorado has a stricter law than some other states and shouldn't have to honor other permits.

The Senate scheduled a vote Wednesday on the measure, which South Dakota Sen. John Thune has included as an amendment to a major defense policy bill.

Backers say truckers and others with concealed-weapons permits should be able to protect themselves in other states.

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