Thanks to the rapidly rising number of vote-by-mail ballots, California’s political animals will be getting to bed a lot earlier on election nights.

That doesn’t mean things will change for supporters and opponents of tightly fought measures like the Prop. 29 cigarette tax, which is losing by 50,000 votes with hundreds of thousands of last-minute mail ballots still to be counted. You can bet that the tobacco czars who plunked some $40 million into the opposition campaign will be spending some sleepless nights until the result is final.

But the vast majority of California races were decided by a couple of minutes after 8 p.m., when county registrars hit the button to release the flood of mail ballots that already had been counted.

Take San Francisco, for example, where I spent election night watching a pair of local ballot measures.

Prop. A, which would have changed the city’s garbage contracts, was expected to lose badly, and did. The first results from the 60,000 or so mail ballots showed 77 percent of the voters opposed.

Now in politics, hope springs eternal and it wasn’t that many years ago that backers of the measure could have – almost – explained away those early results by saying they only represented a small number of more conservative voters and there were still plenty of votes left to count.

Only these days, there really aren’t that many votes left. By the end of the night, with all the precincts reporting, the vote total was 108,865 and the “no” vote was just under 77 percent.

What about a closer race, like San Francisco’s Prop. B to improve Coit Tower? The first vote-by-mail ballots had it winning with a bit less than 54 percent of the vote and the final tally showed it with just about the same percentage.

When I started covering politics, the real experts on election night were the guys – and they were mostly guys – who could follow the results from across the state, seeing where the votes were coming from, which counties were slow with their returns and what that meant for Democrats and Republicans, liberals and conservatives.

The old pros could tell their bosses not to be so quick to predict a GOP win when Democrat-rich Los Angeles still had half the vote out, or to hold off on that Democratic victory speech until San Diego and Orange County had been heard from.

But a recent survey by the Field Poll predicted that Tuesday’s election would be the first presidential primary where most of the votes were cast by mail. And with more and more voters signing up to get their ballots by mail, that percentage of mail votes is only going to grow.

It’s a basic rule in statistics that the larger the sample size, the more likely it is to resemble the population as a whole. So while the results from the 5 percent of voters who cast mail ballots in 1980 – or maybe, if you squint a little, even the 23 percent in 1996 — could be explained away as an older, more Republican and conservative-leaning sample than the California electorate as a whole, what happens when that vote-by-mail number reaches 55 percent, as it likely did Tuesday? Or goes even higher, as it almost certainly will in future elections?

While there’s always a margin of error, experts will tell you it’s none too large a number when the sample is 55 percent of the total. And even with regional differences and the other variables in voting behavior, the result from that first rush of votes is likely to hold up in all but the closest elections.

So say goodbye to those long, late nights of watching the results trickle in and hoping against hope your candidate can reverse the trend of those early ballots.

These days, there are no early ballots. Those mail votes don’t represent a trend, but are the new concrete reality of California elections.

When more than half the ballots are counted and posted minutes after the polls close, the lights are going to be turned off a lot earlier in those election night ballrooms.

John Wildermuth is a longtime writer on California politics.