dayton ohio secret service officer rush stage protect u.s. republican presidential front-runner donald trump disturbance rally saturday day rowdy protest shut event chicago trump briefly duck podium four secret service members scramble surround man charge stage dayton international airport ohio officer grab man dress black t-shirt jeans able reach stage haul away ready know would do well would fight folks trump tell rally late day say man look harm incident increase tension trump chicago rally scrap amid chaotic scenes friday trump republican rival hurl scorn new york billionaire say help create nervous atmosphere sweep race white house fiery rhetoric trump blame supporters democratic candidate bernie sanders incidents chicago scuffle break protesters backers real estate magnate call u.s. senator vermont communist friend scenes chicago follow series recent incidents violence trump rally protesters journalists punch tackle hustle venues raise concern degrade security lead nov. election sudden plan attack come nowhere trump say dayton describe events chicago call protest leaders professional people sanders u.s. senator vermont hit back case virtually every day donald trump show american people pathological liar obviously appreciate supporters trump rally chicago campaign organize protest president barack obama tell fundraise event dallas political leaders try bring us together turn us one another democratic front-runner hillary clinton draw criticism release initial statement mention trump name tie violent campaign events shoot south carolina black church last year leave people dead campaign st. louis missouri saturday clinton criticize trump directly ugly divisive rhetoric encourage aggression violence months-long republican race may come head nominate contest tuesday trump seek victories might give almost insurmountable lead nomination primaries florida ohio particularly important since winner-take-all state republican delegate give winner popular vote instead award proportionally make-or-break day republican candidates john kasich governor ohio u.s. senator marco rubio florida must win home state forge credible path forward trump draw fervent support well criticism call build wall along u.s.-mexico border impose temporary ban muslims enter country rally often attract small group protesters friday first may many protesters supporters event kansas city saturday trump urge police arrest people disrupt events explain mom dad police record get job know go start press charge people problem say cheer outside rally police break confrontations trump supporters protesters shout shut police horseback riot gear briefly move crowd protesters officer use appear pepper spray demonstrators second rubio accord new york time slightly edge kasich saturday win washington d.c. primary 37 percent vote bemoan state presidential race event florida say become reality television last night chicago saw image make america look like third world country rubio say remind supporters stake tuesday high kasich tell journalists campaign event cincinnati ohio trump create toxic environment republican candidate u.s. senator ted cruz texas call chicago incidents sad vanderbilt university political scientist john geer say tension display trump events proxy go electorate writ large people strong reactions donald trump geer say play vote booth also play events geer say chicago cancellation would likely embolden trump supporters idea float trump several television interview clinton pick four delegate northern mariana islands democratic primary saturday sanders two republican side cruz around two-thirds vote wyoming republican nominate contest state unusual rule clear many wyoming delegate go way republican convention july additional report alex dobuzinskis los angeles kevin murphy kansas city idrees ali amanda becker washington edit alistair bell sandra male article fund part sap independently create reuters editorial staff sap editorial involvement creation production new disturbance trump rally crucial republican contest near