A Post-Primary Rally Boosts Trump, Albeit With Challenges Aplenty (POLL)

— -- A new ABC News/Washington Post poll shows a close contest in presidential election preferences, with Republicans lining up behind Donald Trump as their party’s presumptive nominee while the continued Democratic race is keeping Hillary Clinton’s side more unsettled.

Greater voter registration among Republicans is one factor: Clinton’s 6-point lead among all adults, 48-42 percent in a general election matchup, switches to essentially a dead heat among registered voters, 46 percent for Trump, 44 percent for Clinton. Regardless, the contest has tightened considerably since March, when Clinton led among registered voters by 9 points.

See PDF with full results here.

Trump’s enhanced competitiveness reflects consolidation in his support since his primary opponents dropped out, and it comes despite significant challenges to his candidacy. Fifty-eight percent of Americans call him unqualified to be president, 60 percent see him unfavorably overall, 76 percent think he doesn’t show enough respect for those he disagrees with and 64 percent say he should release his tax returns (with most feeling strongly about it). These include majorities of registered voters on each item, representing opportunities for Clinton.

Republicans and Republican-leaning independents, moreover, split 46-46 percent on whether or not Trump represents the core values of the party. That’s sharply improved from 29-56 percent in July, but it leaves the party still divided on a key measure of Trump’s suitability.

Clinton has challenges of her own –- 53 percent of Americans (and 57 percent of registered voters) see her unfavorably, making this a matchup between the two most unpopular likely presidential candidates in the history of ABC/Post election polls, dating back to 1984.

Indeed, half of each candidate’s supporters are negative voters, saying they oppose the other candidate more than they support their own choice. Fewer than half on either side back their candidate strongly. And while 51 percent of Americans say they’d be satisfied with a Clinton-Trump race, 44 percent say they’d want a third-party candidate to run.

Most potential voters, though, seem committed in opposition, if not in support. Marking the level of cross-party antipathy in this contest, 86 percent of Trump supporters say they’d never consider voting for Clinton –- and 86 percent of Clinton supporters say the same about Trump.

The continued Democratic primary race appears to be sapping some of Clinton’s strength in this poll, produced for ABC by Langer Research Associates. She’s losing 20 percent of Bernie Sanders’ supporters to Trump, while winning only 11 percent of leaned Republicans who backed someone other than Trump for their party’s nomination.

Remarkably, Clinton is only running evenly with Trump among 18- to 29-year-olds –- a key Sanders support group that’s looking ever-more resistant to her nomination. In March, Clinton led Trump among under-30s by 39 percentage points, 64-25 percent. Today they split 45-42 percent. It’s a group Barack Obama won by 23 points in 2012, and one that Clinton needs back.