(Yahoo News) — In his final news conference of the year, President Obama heralded the accomplishments of the lame-duck Congress, calling the last six weeks a “season of progress” that proves Washington can rise above political partisanship.

“If there’s any lesson to draw from these past few weeks, it’s that we’re not doomed to endless gridlock,” Obama said. However, the president also voiced his “disappointment” over Congress’s failure to move an immigration measure the White House had flagged as a first-term priority.

In the weeks since his party took a “shellacking” in the midterm elections, Obama has signed a bipartisan bill extending both the so-called Bush tax cuts and jobless aid for Americans who are out of work. On Wednesday, he signed into law a measure repealing the “don’t ask, don’t tell” policy that bans gays from serving openly in the military. And just before his press conference, the Senate voted to ratify the START nuclear-arms treaty with Russia, one of the president’s top foreign policy goals this year — while reaching an accord on the bill to extend health benefits to 9/11 first responders who have taken ill.

Still, Obama didn’t get everything he wanted.

He admitted his “biggest disappointment” was that Congress failed to pass the so-called DREAM Act, which would provide a path to citizenship for illegal immigrants brought to the U.S. by their parents.

He said that it’s “heartbreaking” that the current system forces some children to live in “the shadow of fear” — while also touting his own administration’s record of tough border enforcement and deportation.