John McCainJohn Sidney McCainThe Hill's Morning Report - Democratic debates: Miami nice or spice? Trump pick brings scrutiny to 'revolving door' between Pentagon, industry Trump endorses McSally in Arizona Senate race MORE and Barack ObamaBarack Hussein ObamaBiden has a lot at stake in first debate Biden to debate for first time as front-runner John Kerry: Play based on Mueller report is 'an act of public service' MORE are tied in Ohio, according to a Public Policy Polling survey.
Both men receive 45 percent of the support of voters, 10 percent of whom remain undecided. The Democrat had led in PPP Ohio polls in June and July.

While McCain gets the backing of nearly nine in 10 Republican voters, Obama gets the support of only three quarters of Democrats. Obama leads among independents.

Many of the Democrats who aren't supporting Obama "are disproportionately white, female, and middle aged, an indication that it could be former supporters of Hillary ClintonHillary Diane Rodham Clinton5 things to watch in the Democratic debates Democrats leery of Sanders plan to cancel student loan debt Mellman: Are primary debates different? MORE who are holding out," according to the pollster's analysis.

"Ohio is one state, along with Pennsylvania and Michigan, where Barack Obama would probably be well served by some joint appearances with the Clintons," wrote Dean Debnam, PPP's president. "Democrats have a party ID advantage in Ohio but that won