Vice President Joe Biden applauds as President Barack Obama speaks about immigration reform, Thursday, Oct. 24, 2013, in the East Room of the White House in Washington. The president said now that the partial government shutdown is over, Republicans and Democrats should be able to work together to fix what he called "a broken immigration system." WASHINGTON (AP) - President Barack Obama called on Congress Thursday to finish work on an immigration overhaul by the end of the year, a lofty goal that will be difficult to meet given the staunch opposition of many House Republicans. While immigration remains one of Obama's top second term priorities, the issue has been overshadowed for months, most recently by the 16-day partial government shutdown. The president's shift to a greater focus on immigration came as the White House was seeking to shift the conversation away from the deeply problematic rollout of Obama's health care law. In a talk at the White House, Obama insisted that Congress has the necessary time to finish an immigration bill by the end of the year. The Senate passed sweeping legislation this summer that would provide an eventual path to citizenship for some 11 million immigrants living here illegally and would tighten border security. But the measure has languished in the GOP-led House. "It doesn't get easier to put it off," Obama said, during an event in the East Room. The White House was buoyed by comments this week from House Speaker John Boehner, R-Ohio, who said he was optimistic his chamber could act on immigration by year's end. But Boehner has long had trouble rallying support from the conservative wing of his caucus and it's unclear whether he can get their backing for the comprehensive bill Obama is seeking. Most House Republicans have said they prefer a piecemeal approach to fixing the nation's fractured immigration system.