As the nation's 538 electors cast their ballots for president in 50 states and the District of Columbia on Dec. 19, some protesters continued to make the case for electing someone other than Donald Trump. (Sarah Parnass,Victoria Walker/The Washington Post)

In a world of useless election stats, there has been one floating around that can make a legitimate claim to being the most useless of all. It got fresh pickup over the weekend thanks to Investor's Business Daily, and former congressman Joe Walsh (R-Ill.).

Here it is, via Townhall:

And here's Walsh's much-maligned tweet:

The stat, while meaningless, is not untrue. Without Hillary Clinton's 4.3 million-vote margin in California, her 2.9-million-vote popular vote win becomes a 1.4 million-vote loss (rounding is involved here).

Which shouldn't be too surprising. As Philip Bump notes, when you lop off a state that is home to about 1 in every 8 Americans, things are bound to look a bit different. But why stop there, when there is a virtually endless array of similar pointless stats to contemplate:

Exclude the Deep South, for example — a region that encompasses one-seventh of the country (if you loop in Florida) — and Clinton's margin of victory swells by 1.8 million.

Or, a better example, in the phrasing of Mr. Walsh: “I know Texas is a state & we have to count it, but if you flip TX, Clinton won the electoral vote by 2.”

Unfortunately for Clinton, that's not how it works.

But there's a reason Trump supporters would like to get rid of California's total in particular. It's not just the state's sheer size, or its cities full of godless Hollywood liberals; it's because California voted sharply against Trump in an unexpected way.

After going for President Obama by 24 points in 2008 and 23 points in 2012, California went for Clinton by a whopping 30 points this year — the second-biggest shift toward the Democrats in a year in which most states moved toward Republicans (Trump won and Mitt Romney lost, after all). The only state featuring a bigger shift was Utah, which was due to the strong third-party candidacy of Evan McMullin and Trump's unpopularity among Mormons.

While California was Obama's eighth best state, it was Clinton's third-best, behind only the District of Columbia (still not a state) and Hawaii. It surpassed true-blue states like Massachusetts, Maryland, Rhode Island and Vermont on this year's list.

Clinton's raw-vote margin in California was bigger than Obama's by about 42 percent — 4.3 million vs. 3 million. Again, these were elections in which Obama won the national election and Clinton lost.

In perhaps the most striking stat I've seen, seven GOP House candidates — half of the delegation's Republicans — won their districts despite Clinton carrying them, according to Greg Giroux:

We still don't have the presidential vote in each congressional district, but Daily Kos Elections' David Nir has been crunching the numbers and has so far found only seven other so-called Clinton-Republican districts out of 216 nationwide (not including California). In other words, half of the Clinton-Republican districts so far have been in this one state.

The Washington Post explores Donald Trump's transformation from a reality TV star to president-elect of the United States. (McKenna Ewen,Whitney Shefte,Dalton Bennett/The Washington Post)

So the question there is why. Why did California shift so strongly against Trump? Is it just demographics — or could there be some other factor at work?

There could. One very plausible theory is that GOP turnout was hurt by the lack of a Republican candidate in the state's open Senate race. California now has a system in which the top two primary candidates advance regardless of party — and this year, that meant two Democrats. I noted this possibility recently:

The Senate race in California featured two Democrats, and there wasn't another statewide race featuring a Republican, except for president (which was a foregone conclusion). In other words, there perhaps wasn't as much reason for Republicans to turn out to vote.

Did this depress GOP turnout? Maybe. In 2012, exit polls showed Republicans were 27 percent of the state's electorate; this year, they were 23 percent.

There's also the fact that the state as a whole seems to be drifting toward Democrats. Since Obama was first elected in 2008, the number of registered Democrats has risen by 1 million, while the number of registered Republicans has dropped by about 350,000.

But judging by the numbers above — and the willingness of Californians in seven congressional districts to vote for Clinton even while returning their GOP members to Congress — it seems something about Trump is uniquely unappealing to California and even its GOP-leaning voters.

It may be only a matter of time before Trump proposes its expulsion from the union.