Call it the old one-two punch for New York. This morning, New Yorkers awoke to find that their primary elections, set for Thursday, had been canceled. Problems with the Voting Rights Act. This afternoon, about 3:30, another surprise: in parts of lower Manhattan, the lights went out.

The New York Stock Exchange, which had been having a slight rally, was forced to shut down. The elevators at Macy's got stuck. Subway service floundered. Traffic lights along Wall Street and sections of the lower west side simply went out. In Greenwich Village, kids in sneakers stepped into the middle of the street to direct traffic.

At City Hall, where Mayor Edward Koch had been discussing the election crisis earlier, the lights also failed. The mayor, who had been scheduled to run in the primary on both the Republican and Democratic tickets, was merely amused. Something to get the town's mind off the election troubles, he joked. Then he left. Reason: "To get a beer."

Mild confusion and traffic jams reigned. Koch declared a "Phase-Three Emergency," and dispatched himself to the Brooklyn Bridge (his favorite spot in an urban crisis) to wish well to the schleppers who were walking home.

But the general feeling among New Yorkers, who, after all, have gone through two city-wide blackouts, was nonchalance. This blackout, caused by a fire in a Consolidated Edison plant, and affecting 52,000 customers, was not considered major.

By early evening power had been restored. The fire was declared under control at 6:04 p.m. A Con Ed spokesman said the company did not know what caused the crippling explosion at the east side power station.

Meanwhile, after facing days of a declining stock market, investors who hoped to cash in on the late rally on the New York Stock Exchange were stymied. Although some stocks listed on the New York exchange can be bought on other exchanges, when the Big Board is closed it is difficult for investors to buy or sell most of the nation's important stocks.

"You couldn't compare this to the '77 blackout," said Con Ed aide Virginia McLaughlin, referring to one of the city's greats. In that blackout, as people were quick to reminisce, almost the entire city was blacked out for 25 hours, and there was looting. In '65, a sudden power surge, triggered by a relay failure at a power station in Canada, took out all of New York City, New England and parts of Ontario, but it is hard to feel proprietary there. It was not, after all, a crisis exclusive to New York.

Thus, New Yorkers, with perhaps the exception of the 100 or so the police had to free from elevators, seemed to take the affair in stride.

"You know the drill," said Lewis Grossberger, a Greenwich Village writer who was at home when the lights went out. "You got to check the flashlight, which you haven't used since the last blackout, you go get a new typewriter ribbon because you have to switch from electric to manual, you go out in the street, this is maybe 15 minutes later, and there are at least 12 people ahead of you at the store, buying candles, making jokes. They're very practical. They've seen it before."