AFP—Democrats retook Republican strongholds in New York’s city hall and the Virginia governor’s mansion Tuesday, while a Republican with potential presidential hopes won re-election easily in New Jersey.

Tuesday’s vote was the first major round of balloting in the United States since President Barack Obama won a second term in the White House last year. Some races were seen as litmus tests for future national voting.

In the nation’s largest city, New York, old-style progressive Bill de Blasio became its first Democratic mayor in a generation, specifically since 1989, even though New York is overall largely Democrat.

Another key race, for the governorship of the southern state of Virginia, turned out to be a nail-biter, but in the end Democrat Terry McAuliffe won in the otherwise strongly Republican state bordering the nation’s capital.

In other states, lesser issues like marijuana were on the ballot.

Portland in the state of Maine on the east coast legalised it for people over 21, joining other cities which have done so. But this was unprecedented on the East Coast.

And in Colorado, where the herb was recently legalised, voters agreed to tax sales of it.

New Jersey’s Republican Governor Chris Christie handily defeated his Democrat challenger, earning a second four-year term in a race some pundits said would serve as a platform for a future presidential bid.

Christie is a straight-talking moderate Republican who won much praise for his handling of the devastation wrought on his state last year by Superstorm Sandy.

He cruised to a landslide win even though he is at odds with many in his party at the national level.

At a raucous victory rally, Christie promised yet more pragmatic leadership.

“We stand here tonight showing that it is possible to put doing your job first, to put working together first, to fight for what you believe in yet still stand by your principles and get something done for the people who elected you,” he declared.

He is increasingly seen as a contender for the Republican nomination for the White House in 2016 given his pragmatism, charisma and ability to command cross-party support.

Obama called De Blasio, McCauliffe and Boston mayor-elect Martin Walsh to congratulate them.

Meanwhile, the race in the Big Apple — in which de Blasio long had been tipped as the heavy favourite to replace billionaire Michael Bloomberg — was one of several seen as a barometer of public opinion ahead of congressional elections in 2014.

De Blasio, 52, promises a new style in a city transformed by 12 years of tough love under Bloomberg, a Republican-turned-independent who is stepping down after a record three terms.

“Our work is really just beginning,” De Blasio told supporters at his Brooklyn campaign headquarters in his victory speech.

One of his key focuses is to narrow the gap between rich and poor in the nation’s financial hub.

“The challenges we face have been decades in the making. And the problems we set out to address will not be solved overnight. But make no mistake — the people of this city have chosen a progressive path — and tonight we set forth on it — together as one city,” de Blasio said in a speech delivered in both Spanish and English.

He left Republican rival Joe Lhota trailing in the dust in the biggest city in the United States by tapping into the worries of the economically vulnerable middle class.

He promises to raise taxes to fund universal pre-kindergarten education and after-school programmes, and build 200,000 affordable housing units.

The incoming de Blasio administration is likely to usher in a dramatic change in the mayor’s office led by Bloomberg, a transformative figure, but who leaves behind an electorate divided over his legacy.

There has been a continued reduction in violent crime and his aggressive public health policies, such as banning smoking in bars and restaurants, have been copied in many cities.

Meanwhile, Virginia’s changing demographics — with a rural-suburban split and significant military and government employee populations — make it a litmus test for the political mood ahead of the next presidential vote in 2016.

Christie’s win, paired with Cuccinelli’s loss, is likely to solidify thinking that Republicans would be better served with ditching deeply ideological candidates.

Mayoral elections were also held Tuesday in the rustbelt city of Detroit, which recently declared bankruptcy. Democrat Mike Duggan won, though his job holds little power as the city is now run by a state-appointed emergency administrator.

In Boston, traumatised by the Boston Marathon bombings in April, Democrat Walsh replaced outgoing Mayor Thomas Menino.

Menino, also a Democrat, departs after 20 years in office, the longest in Boston mayoral history.

Out in Colorado in the west, six of 11 counties voted to ask authorities to explore the idea of seceding and forming the 51st US state.

Proponents of this move said they were unhappy with the state legislature because of stricter gun laws and new renewable-energy standards.