Clinton has been a vocal proponent of increasing measures to prevent criminals and the mentally ill from being able to buy guns, bear-hugging gun control throughout the primary. On Tuesday, she donned an orange shirt for national "Wear Orange" National Gun Violence Awareness Day. She's effectively used guns as a wedge issue against Bernie Sanders, who has a more mixed record on gun control. Trump, who had previously backed some gun control measures, has swung hard to the right on the issue.