US Congress " is moving to right a centuries-old wrong"

The United States Congress has supreme authority over Washington, D.C.; residents of the city therefore have less self-governance than residents of the states. The District has a non-voting at-large Congressional delegate, but no senators. D.C. residents could not vote in presidential elections until the ratification of the Twenty-third Amendment to the United States Constitution in 1961.

The House is expected to pass the measure with a strong majority next week and President Barack Obama, a co-sponsor when the bill failed to clear the Senate two years ago, has promised to sign it.

The measure is likely to face a court challenge immediately after becoming law; opponents argue that it is unconstitutional because D.C. is not a state and does not qualify for representation.

Sen. Joe Lieberman, a Connecticut independent, who sponsored the bill with Sen. Orrin Hatch, R-Utah, expressed confidence that they could win the legal argument and noted that the bill contained an expedited appeals process to ensure a quick court decision.

The real issue, he said, is that the disenfranchisement of 600,000 residents of the nation's capital "is patently unjust and un-American in a sense of the best principles of this country."

"This is a historic moment," said Ilir Zherka, head of the advocacy group DC Vote. "In 2007 we were gaining tremendous momentum," he said. "The huge difference this year is that we have an advocate in the White House."

Two years ago, with Democrats holding a smaller majority in the Senate and then-President George W. Bush threatening a veto on constitutional grounds, the Senate fell three votes short of overcoming a GOP-led filibuster.

Under the rules of debate Thursday, supporters needed 60 votes to win passage. Six Republicans voted for the measure while two Democrats opposed it.

Article One of the United States Constitution provides for a federal district, distinct from the states, to serve as the permanent national capital. The centers of all three branches of the federal government of the United States are located in the District, as are many of the nation's monuments and museums. Washington, D.C., hosts 174 foreign embassies as well as the headquarters of the World Bank, the International Monetary Fund (IMF), the Organization of American States (OAS), the Inter-American Development Bank, and the Pan American Health Organization (PAHO). The headquarters of other institutions such as trade unions, lobbying groups, and professional associations are also located in the District.