Why a Meaningful Shift in the Trump-Clinton Race May Be at Hand
By NATE COHN
Hillary Clinton has a large and perhaps growing lead in the nation and in many of the predominantly white battleground states where Donald Trump was thought to have his best shot, according to a wave of new surveys released in the last two days.
Three national surveys — from Fox, NBC/WSJ and Marist/McClatchy — showed Mrs. Clinton ahead by big margins: 10, 9 and 15 percentage points. It’s the worst polling stretch for a presidential candidate at this stage since John McCain in mid-October of 2008.
It’s a little hard to make sense of it all, in part because the timing is a little unusual. This ought to be the heart of Mrs. Clinton’s post-convention bounce, when polling analysts generally preach caution. On the other hand, Mr. Trump had a tough week of his own making — drawing condemnation from Republican leaders and even causing a few high-profile defections from donors and the conservative media.
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The prudent approach is to wait, and see whether Mrs. Clinton’s lead endures for another week or two — after convention bounces usually fade. In the interim, we can cautiously say that there is more reason than usual to think that Mrs. Clinton’s newfound lead represents a meaningful shift in the race, one that would make a comeback for Mr. Trump seem daunting if it holds.
In general, it’s not worth overthinking post-convention bounces. They don’t necessarily even reflect real shifts in voter attitudes, just changes in how likely people are to respond to surveys. But strong conventions can speed up unification of divided parties and usher in a real shift.
Part of the reason Mrs. Clinton’s bounce seems more likely to last is that it seems to be coming from greater party unity: growing support from Bernie Sanders’s backers. The Marist poll showed Mrs. Clinton with the support of 90 percent of his voters, while a CNN poll gave her 91 percent. These numbers had usually been in the 60s or 70s.
Mrs. Clinton’s support appears to be underpinned by her improving image among Democratic-leaning voters, according to Gallup data. She could still lose some of those voters to third-party candidates, but Mr. Trump faces similar risks.
These gains have allowed Mrs. Clinton to move up to around 47 or 48 percent of the vote in recent polls. This is not an especially impressive tally, but for that same reason it seems reasonable to expect she could keep it: She’s not winning the support of a huge number of voters whom you would expect to abandon her.
At the same time, the unusually large number of voters considering a third-party candidate make Mrs. Clinton’s tallies seem likelier to be enough to win.
The polling numbers for Gary Johnson or Jill Stein will probably decline — especially once likely-voter screens are added. Mrs. Clinton’s tally would probably improve in the process; some of those voters would drift to her, and her voters would become a larger share of likely voters.
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The only polls that matter are those on the eve of the election. My advise is to chill out.