When national media outlets need to know what’s going on in Nevada politics, they often turn to Las Vegas–based journalist Jon Ralston, who’s developed a strong track record of calling elections in the state.

And now that Nevada early voting has come to a close, Ralston isn’t mincing words about how he sees Donald Trump’s prospects. “Trump is dead,” Ralston tweeted Saturday. He elaborated on his blog that from the early voting numbers so far, the GOP nominee would need a “miracle” to win Nevada at this point.

The polls have tended to put Nevada as a pure toss-up state, and a few recent ones have even shown Trump ahead there. Accordingly, it hasn’t generally been considered part of Hillary Clinton’s swing state “firewall.”

But Nevada is a famously difficult state for national pollsters to get right. Its population is transient, and many work at night. Furthermore, its population is more than one-quarter Hispanic, and it’s often challenging for English-language polls to sample Hispanic voters accurately.

In both of the past two presidential elections, polls underestimated Barack Obama’s eventual margin of victory in the state. And in Harry Reid’s 2010 Senate campaign, the polls utterly whiffed, suggesting he’d lose to his challenger Sharron Angle when he ended up winning by nearly 6 points.

So in previous years, analysts like Ralston have found success in reading tea leaves from Nevada’s early voting numbers instead. And all week, Ralston has been warning of danger signs for Trump. The partisan and geographic breakdown of early voting turnout has looked similar to 2012, when Obama won the state by 6.5 points. But the final day of early voting Friday was, Ralston writes, “cataclysmic” for Republicans.

Why Ralston believes Trump is doomed in Nevada

Ralston is looking at two main things — the numbers of registered Democrats who have voted compared with registered Republicans, and the geography of the turnout.

Though the statewide early voting numbers aren’t yet finalized, Ralston estimates that registered Democrats will have a 6-point lead on registered Republicans among early voters. Since registered partisans tend to overwhelmingly vote for their own party, Trump probably either needs to dominate among early voters associated with neither party or else make up the gap on Election Day.

Ralston flags the numbers from Clark County, which contains Las Vegas and three-quarters of the state’s population and is where Democrats have drawn much of their support. So far, he writes, 73,000 more registered Democrats turned out than registered Republicans in Clark — and if those voters back their party’s candidates, that’s a big lead in raw votes that will be very difficult for Republicans to overcome with the more sparsely populated counties elsewhere. (In 2012, Obama beat Mitt Romney statewide by about 70,000 votes.)

Anecdotally, there appears to have been very high turnout among Hispanic voters in Clark on Friday, which led Ralston to tweet:

Hispanics waiting on line for hours to vote against Donald Trump in the state that could block him from the presidency is just too much. — Jon Ralston (@RalstonReports) November 5, 2016

We should caution that we do not technically know whom these people voted for. If these registered partisans did not vote overwhelmingly for their own party, if non-party-affiliated voters break overwhelmingly for one candidate, or if Election Day turnout looks dramatically different, Ralston’s call might not pan out.

But ballots equivalent to well over two-thirds of the total 2012 turnout in Nevada have already been cast. So if Trump has indeed fallen significantly behind in the early vote, it will be very challenging for him to catch up.

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