Essential Politics: Clinton stumbles in polls — a temporary blip or new normal?

This morning, with our partners at USC, we launched our new Daybreak tracking poll of the presidential election, and it starts out with Donald Trump holding a slim lead over Hillary Clinton.

That differs from the polling averages, which continue to show Clinton leading Trump, but it’s consistent with a flurry of other polls released in the last several days that show Clinton’s lead declining, or vanished, since the sharp criticism that FBI Director James Comey aimed at her handling of classified information while she was secretary of State.

The big question now is whether the decline is short-lived, to be followed by a return to the status quo of Clinton holding a persistent lead over Trump, or whether the email issue has created a new opening that Trump can use to change the contours of a race he’s been losing. The next couple of weeks, with the vice presidential picks and the party conventions, could be a pivotal phase of the campaign. You can follow our tracking poll every day through the election on our politics page.

Good afternoon, I’m David Lauter, Washington bureau chief. Welcome to the Friday edition of our Essential Politics newsletter, in which we look at the events of the week in the presidential campaign and highlight some particularly insightful stories.

THE CLEVELAND CONVENTION — NO WATER PISTOLS ALLOWED

Republicans already have started to gather in Cleveland, where the party’s platform and rules committees have spent the week deliberating.

Our politics team will be there in force, so keep up with all the latest developments on Trail Guide and check our Politics page for analysis, insight and video excerpts of the key speeches.

The convention’s rules committee on Thursday wiped out the last chance that the party’s #NeverTrump faction had for blocking Trump’s nomination. Melanie Mason and Lisa Mascaro were there to chronicle how the deal went down.

As for the party platforms, Mason and Chris Megerian, who covered the negotiations between the Clinton and Bernie Sanders camps over the Democratic platform meetings, had a careful look at why platforms often really do matter, and why they’re so darn long.

In addition to the debates and speeches inside the convention hall, the GOP gathering is also expected to feature large-scale protests.

Cleveland police issued regulations on Thursday covering “prohibited items” in the protest areas near the convention side. As Matt Pearce, noted, tennis balls and chains are banned. So are water pistols. But real guns? Guns are fine. Ohio has an open-carry law, so the city police can’t confiscate firearms.

THE VEEPSTAKES CONTINUE

To twist a line from Descartes, Indiana’s governor could declare yesterday, “Je Pence, donc je suis”: I am Pence, therefore I am. But am what? Running mate presumptive? Maybe.

As Mark Barabak and Michael Finnegan chronicled, Thursday was a day of wild, seemingly chaotic suspense, as Trump, making repeated calls to different cable television hosts, stirred the pot over this vice presidential selection while Mike Pence, having told associates that he had the nod, cooled his heels at a Manhattan hotel.

Friday morning, Trump finally ended the show, sending a Twitter message saying that he had, indeed, chosen Pence, turning aside former House Speaker Newt Gingrich and Gov. Chris Christie of New Jersey.

The Democratic side has proceeded more sedately. Evan Halper was in Virginia on Thursday as Clinton campaigned with Sen. Tim Kaine, who appears to be the front-runner for the second spot on her ticket. Other names continue to be floated, however.

Clinton is likely to make her announcement at the end of next week, after the GOP convention winds up.

Clinton’s running mate deliberations come amid mixed political news for her. On the one hand, Comey’s criticism has clearly had a negative impact. On the other hand, Tuesday brought the long-awaited endorsement from Sanders and with it, the hope of unity within the Democratic Party.

Already, Clinton has gotten significant backing from Sanders voters. If the official endorsement brings along another big batch of his supporters, that would provide a meaningful boost for her.

But full unity is probably not in the cards. Some of Sanders’ convention delegates openly criticized his decision. His longtime friend Cornel West, who represented Sanders on the Democratic platform committee, wrote in the Guardian that he would back Green Party nominee Jill Stein.

And as Seema Mehta discovered by analyzing voter data, a notable percentage of Sanders’ delegates are newcomers to the party.

A SUPREME MISTAKE, A PRESIDENTIAL PHONE BILL

David Savage chronicled the controversy that broke out when Supreme Court Justice Ruth Bader Ginsburg publicly criticized Trump in a series of interviews with reporters. Ginsburg, the court’s leading liberal, was scathing, and her words broke a longstanding tradition of the high court’s members staying away from electoral politics.

On Thursday, Ginsburg admitted error, saying her words had been “inappropriate.”

Finally, Halper took a look back at what happened when Bill Clinton agreed to give speeches at an event hosted by a California college. The fallout included a $1,400 phone bill, a $700 dinner for two and a lot of bruised feelings.

DON’T FORGET THE ELECTORAL COLLEGE

The popular vote is all very well – just ask Al Gore –but gaining the presidency requires winning enough states to get 270 electoral votes. How to get there? Play political strategist for yourself, and try out as many scenarios as you like on our electoral map.

QUESTIONS ABOUT TRUMP OR CLINTON? WE’VE GOT ANSWERS

Where they stand on issues, what they’ve done in their lives, their successes, their failures, what their presidencies might look like: We’ve been writing about Clinton and Trump for years, and we’ve pulled the best of that content together to make finding what you want to know easier. So check out All Things Trump and All Things Clinton.

LOGISTICS

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That wraps up this week. My colleague Christina Bellantoni will be back Monday with the weekday edition of Essential Politics. Until then, keep track of all the developments in the 2016 campaign with our Trail Guide, at our Politics page and on Twitter @latimespolitics.

Send your comments, suggestions and news tips to politics@latimes.com.

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