The letter to the mayor's organization was opened by Mark Glaze, director of Mayors Against Illegal Guns, in Washington on Sunday.

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The opinions expressed in this commentary are solely those of Mark Glaze.

CNN: Americans, even NRA members, want gun reforms

"I'm not sure the public mood is going to improve on this anytime soon, " said Mark Glaze, the executive director of Mr. Bloomberg's group.

WSJ: Mayor's 2014 Gun Push

"Opposing yet another reform, which has Americans scratching their heads, is not a place where a national political party can afford to be, " said Mark Glaze.

NPR: Boost For Background Checks: Senators Compromise

The second letter to the mayor was opened by Mark Glaze, director of Mayors Against Illegal Guns -- founded and co-chaired by Bloomberg -- in Washington on Sunday.

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