WASHINGTON (AP) — Donald Trump regularly warns his crowds to closely watch polling places to prevent Democrats from stealing the election. [...] his campaign has failed to enlist many to serve as official poll watchers in major population centers, according to spot checks by The Associated Press. While specific rules vary from state to state, poll watchers generally are registered voters appointed by the campaigns to sit in polling places and observe. DeFelice said he is concerned about how Republicans are treated on Election Day in some overwhelmingly Democratic neighborhoods, but said he isn't worried by the absence of more observers. [...] after surveying election officials in Florida's 10 most populous counties, the AP found that Clinton's people far outnumber Trump's. In some of Ohio's biggest population centers, Republicans have preserved their options to send in election observers. In both Cuyahoga and Franklin counties, which Obama won with 69 percent and 60 percent, respectively, local Republican officials have submitted tentative paperwork to have a poll watcher in each of the counties' roughly 825 precincts. Under Ohio's bipartisan election administration system, Republicans and Democrats both share oversight of elections, rendering serious concern about improprieties moot, he said.