David Ryder/Reuters

Kshama Sawant at a rally this month in Seattle. A proposal to raise the city's minimum wage to $15 an hour was central to Ms. Sawant's successful run for a seat on the City Council.  She is one of only a few socialists nationwide to be elected to office.

SEATTLE — People are used to liberals running things around here. But nobody reckoned with Kshama Sawant. Ms. Sawant, a 41-year-old economics teacher and immigrant from India, took a left at liberal and then kept on going — all the way to socialism.

When she takes a seat on Seattle's nine-member City Council on Jan. 1, representing the Socialist Alternative Party, she will become one of the few elected socialists in the nation, a political brand most politicians run from.

But Kshama Sawant (pronounced SHAH-mah sah-WANT) heartily embraces the label. Ask her about almost any problem facing America today, and her answer will probably include the "S" word as the best and most reasonable response. Socialism is the path to real democracy, she says. Socialism protects the environment. Socialism is the best hope for young people who have seen their options crushed by the tide of low-wage, futureless jobs in the post-recession economy.

"The take-home message for the left in general is that people are looking for alternatives," she said in an interview, discussing her victory over a veteran Democrat by a margin of 3,100 votes of about 184,000 cast in a citywide contest. "If you ask me as a socialist what workers deserve, they deserve the value of what they produce."

Progressive liberals — some of whom might look radical as well, at least to conservatives — made inroads in other places on Election Day, notably in New York City, where Bill de Blasio won the mayor's race partly on his plan to address the gulf between the "two New Yorks" of poverty and wealth.

Here in Seattle, Mayor-elect Ed Murray, a former state senator and a leader of the state's drive to allow same-sex marriage, promised support for an idea that was central to Ms. Sawant's campaign: a $15 minimum wage in the city, matching the highest in the nation. He said in an interview that he saw momentum in cities across the country in addressing income inequality.

"The commonality is the expression of a progressive impulse based on the shrinking middle, as more people slip into poverty and as more wealth is concentrated in fewer hands," Mr. Murray said.

Seattle Republicans, mostly watching from the sidelines, also see a trend to the left. They say a socialist on the City Council will probably fit right in.

"I don't think she differs that much from other Council members," the chairwoman of the King County Republican Party, Lori Sotelo, said of Ms. Sawant.

Leftist critiques of capitalism have a long past in the Northwest, historians said, from the Wobblies in lumber camps in the early 20th century, as the Industrial Workers of the World were called, to Seattle's general strike of 1919 and the anarchist movement that still stirs occasionally now. A socialist was elected mayor of Seattle as recently as 1922.

"She tapped into a growing discontent," James N. Gregory, a professor of history at the University of Washington, said of Ms. Sawant. "But she also built off a framework of liberalism and economic liberalism that is pretty widely, strongly based in Seattle."

The spotlight on Ms. Sawant, as one of only a handful of self-avowed socialists to be elected to a city council in a major American city in decades, experts say, could be intense. Her party has supported Ralph Nader for president, but its website also links to the writings of the Bolshevik leader Leon Trotsky. It put up municipal candidates in Boston and Minneapolis this year, though none won. The Socialist Party USA, an older group, regularly fields candidates in state and federal races. Senator Bernard Sanders of Vermont calls himself a socialist, though he was elected as an independent.

"If she remains only an activist, she'll be a one-shot wonder," said the Rev. Rich Lang, the pastor of University Temple United Methodist Church in Seattle and a Sawant supporter. But if she moves too far toward the center, "she'll be shot down from the left as a compromiser," he said. "There's tremendous pressure on her."

So should an elected 21st-century socialist hark back to the old Marxist passions of labor and capital, or more toward the welfare-state model of market regulation and high taxes on the rich?

Ms. Sawant, during the interview, sometimes responded one way, sometimes another.