President Barack Obama has won election to a second term in the White House after a hard-fought campaign against Republican challenger Mitt Romney. Obama, a Democrat, won support in the key battleground states of Colorado, Michigan and Virginia, among others.
As the state-by-state tally was announced, Obama sailed past the 270 electoral votes needed to win the election, scoring victories in the key battleground of Ohio and a series of other states where the vote was closely divided.
In his victory speech in Chicago, he promised action, not politics as usual.
"In the coming weeks and months, I am looking forward to reaching out and working with leaders of both parties to meet the challenges we can only solve together: reducing our deficit, reforming our tax code, fixing our immigration system, freeing ourselves from foreign oil. We've got more work to do," Obama said.
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The gap in the popular vote was close, with Obama winning just over 50 percent of ballots as the vote count continued early Wednesday morning.
But the count in electoral votes was decisive, despite wins by Romney in the battleground state of North Carolina and a swath of states from the South through the Midwest and West, including Indiana, Kansas, Missouri, Texas and Arizona. The United States awards the presidency according to state results, not popular vote.
Romney, conceding the race in Boston, said he had called to congratulate the president, his campaign staff and supporters.
"I wish all of them well, but particularly the president, the first lady and their daughters," said Romney. "This is a time of great challenges for America and I pray that the president will be successful in guiding our nation."
Romney also warned against partisan bickering at a time he called a critical point for the nation.
For the Romney campaign, the key issue in this election was the poor economy and continuing high rate of unemployment. The national jobless rate stands at nearly eight percent, but President Obama argued that the economy is improving and that his administration has helped to create jobs.
In Chicago, the president said the nation's promise remains intact. "I believe we can seize this future together because we are not as divided as our politics suggest," Obama added. "We're not as cynical as the pundits believe. We are greater than the sum or our individual ambitions and we remain more than a collection of red states and blue states referring to map designations of Democrats and Republican. We are and forever will be the United States of America."
In congressional races, Republicans held onto their majority in the House of Representatives and Democrats maintained control of the Senate, making gains in Indiana and other states. In the Massachusetts senate race, Democrat Elizabeth Warren defeated Republican incumbent Scott Brown and in Virginia, Democrat incumbent Tim Kaine beat Republican George Allen. In Maine, former governor Angus King, an independent, won the senate seat vacated by moderate Republican Olympia Snowe, who is retiring.
Voters around the country also decided more than 170 ballot measures, approving gay marriage in Maine and Maryland and endorsing the recreational use marijuana in Colorado and Washington, putting those states at odds with federal drug law. In close races around the country, the counting of ballots continues.