Reid later said the ratification solidified Obama's standing as a world leader and Nobel Peace Prize winner.
The treaty, he told The Associated Press, was about the standing of the United States in the world community "and whether Barack Obama was a man who deserved the Nobel Peace Prize, a man who has so turned around American foreign policy."
At the time, some had complained that Obama, less than a year into his presidency, had won the prize prematurely.
Congress also approved legislation to strengthen the safety of the nation's food supply and provide $4.2 billion to survivors of the September 2001 attack on the World Trade Center and responders who became ill working in its ruins.
There were failures in the Democrats' last days of congressional control.
Obama and Reid both said they chafed at the Republicans' defeat of the DREAM Act, legislation that would have provided a path to citizenship for millions of young illegal immigrants.
And McConnell persuaded enough Republicans to oppose a $1.3 trillion omnibus spending bill, forcing Reid to withdraw it. GOP senators had complained about special projects in the bill — some of which they had sponsored — as well as its overall cost and the lack of time for debate. Instead, the two sides agreed to a "continuing resolution" to prevent the government from running out of money for daily operations, through March. Obama predicted a "robust" debate over the matter after the holidays.
Before Obama jetted off to join his family in Hawaii, he was asked about a well-worn campaign riff in which he likened Republicans to people who drove the nation's economy into a ditch.
Obama said the economy is now on level ground. And he left no doubt that the 2012 election will in large part determine the policymaking path forward.
"Both parties are going to be held accountable," Obama said, "and I'm going to be held accountable if we take a wrong turn on that the front."
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