Story highlights President Obama says opposing immigration reform will hurt Republicans politically

He says the GOP risks "losing a generation of immigrants"

Obama says he still plans to take executive action on immigration after the November elections

Republicans are committing political suicide and putting the support of an entire generation on the line by opposing an overhaul of U.S. immigration laws, President Barack Obama said Thursday night.

"It's anybody's guess how Republicans are thinking about this," Obama said during a town hall event in Santa Monica, California. "If they were thinking long-term politically, it is suicide for them not to do this."

"Because the demographics of the country are such that you will lose a generation of immigrants which says, 'That party doesn't seem to care about me,'" he said. "In the short term, they have a problem with the tea party and others who often express virulently anti-immigrant sentiment."

The President repeated his vow to sign an executive order making changes to the immigration system after the November 4 midterm elections. But he said "all the executive authority I legally have" won't be as effective as Congress approving legislation would be.

Obama said he will make visa changes to allow more technically skilled workers to enter the United States, and noted that naturalized Americans have won 25% of the country's Nobel Prizes in the sciences.

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"And so the idea that we would make it harder for talent to come here -- especially when so often that talent is coming to study here, going to school here, wants to stay here, wants to work here, wants to invest here -- makes no sense," he said.

Obama had planned to sign an immigration-related executive order by now as part of his "pen and phone" strategy to bypass a gridlocked Congress. But a flood of unaccompanied children over the U.S.-Mexico border over the summer led the White House to delay that move until after the midterm elections.

House Speaker John Boehner sharply criticized Obama on Thursday for the delay, which he called "raw politics," designed to help endangered Senate Democrats keep their majority.

The Ohio Republican issued a joint statement with House Judiciary Committee Chairman Bob Goodlatte, a Virginia Republican.

"It's shocking that the White House now openly admits that President Obama is delaying his unilateral actions on immigration until after the November elections simply because of raw politics," the two said.

Boehner and Goodlatte said no matter the timing, it's "never acceptable" for presidents to issue executive decrees that rewrite laws.

"By taking unilateral action on immigration, President Obama will inject serious constitutional questions into an already heated debate," the two said. "Such shortsighted actions will undermine the American people's trust in the President's commitment to enforcing our immigration laws and will further set back any chance of enacting immigration reform."