![David J. Phillip FILE - Democratic presidential nominee Al Gore kisses his wife, Tipper, on the stage at the Democratic National Convention in Los Angeles, Aug. 17, 2000. Presidential conventions can be memorable for floor fights and bloody battles on the streets outside, or for scenes that standout as outlandish or awkward. From Clint Eastwood haranguing of an empty chair in 2012 to Gore's uncomfortably long kiss in 2000 and pitched battles between police and protesters outside in Chicago in 1968, conventions past have produced many memorable moments. (AP Photo/ David J. Phillip, File)](https://mapi.associatedpress.com/v2/items/cc0bbf0997cd4b30bb2641fb8df8f707/preview/preview.jpg?s=680x&wm=false)
FILE - Democratic presidential nominee Al Gore kisses his wife, Tipper, on the stage at the Democratic National Convention in Los Angeles, Aug. 17, 2000. Presidential conventions can be memorable for floor fights and bloody battles on the streets outside, or for scenes that standout as outlandish or awkward. From Clint Eastwood haranguing of an empty chair in 2012 to Gore's uncomfortably long kiss in 2000 and pitched battles between police and protesters outside in Chicago in 1968, conventions past have produced many memorable moments. (AP Photo/ David J. Phillip, File)
![Lynne Sladky FILE - Actor Clint Eastwood speaks to an empty chair while addressing delegates during the Republican National Convention in Tampa, Fla., Aug. 30, 2012. Presidential conventions can be memorable for floor fights and bloody battles on the streets outside, or for scenes that standout as outlandish or awkward. From Eastwood haranguing of an empty chair in 2012 to Al and Tipper Gore's uncomfortably long kiss in 2000 and pitched battles between police and protesters outside in Chicago in 1968, conventions past have produced many memorable moments. (AP Photo/Lynne Sladky, File)](https://mapi.associatedpress.com/v2/items/dae2addf5f6541ba84381bf6a496d05e/preview/preview.jpg?s=680x&wm=false)
FILE - Actor Clint Eastwood speaks to an empty chair while addressing delegates during the Republican National Convention in Tampa, Fla., Aug. 30, 2012. Presidential conventions can be memorable for floor fights and bloody battles on the streets outside, or for scenes that standout as outlandish or awkward. From Eastwood haranguing of an empty chair in 2012 to Al and Tipper Gore's uncomfortably long kiss in 2000 and pitched battles between police and protesters outside in Chicago in 1968, conventions past have produced many memorable moments. (AP Photo/Lynne Sladky, File)
![Michael Boyer FILE - Chicago Police attempt to disperse demonstrators outside the Conrad Hilton, Democratic National Convention headquarters, Aug. 29, 1968, in Chicago. Presidential conventions can be memorable for floor fights and bloody battles on the streets outside, or for scenes that standout as outlandish or awkward. From Clint Eastwood haranguing of an empty chair in 2012 to Al and Tipper Gore's uncomfortably long kiss in 2000 and pitched battles between police and protesters outside in Chicago in 1968, conventions past have produced many memorable moments. (AP Photo/Michael Boyer, File)](https://mapi.associatedpress.com/v2/items/77f017f8af574164a5842e67e0195aa7/preview/preview.jpg?s=680x&wm=false)
FILE - Chicago Police attempt to disperse demonstrators outside the Conrad Hilton, Democratic National Convention headquarters, Aug. 29, 1968, in Chicago. Presidential conventions can be memorable for floor fights and bloody battles on the streets outside, or for scenes that standout as outlandish or awkward. From Clint Eastwood haranguing of an empty chair in 2012 to Al and Tipper Gore's uncomfortably long kiss in 2000 and pitched battles between police and protesters outside in Chicago in 1968, conventions past have produced many memorable moments. (AP Photo/Michael Boyer, File)