WASHINGTON (AP) — President Barack Obama’s determination to act alone to change the immigration system promptly drove a wedge Wednesday into the post-election commitment from the president and Republican leaders to find common ground under the new political alignment.

Obama defiantly stood by his pledge to act on his own to reduce deportations, grant work permits and improve border security by the end of the year despite resounding election victories by Republicans strongly opposed to his plans. The Senate’s likely majority leader next year, Mitch McConnell, R-Ky., declared that such a move would amount to “waving a red flag in front of a bull.”

On a day when both sides tried to herald a new era of potential compromise, immigration stood out not only as a single obstacle to bipartisanship but as a sign that the hard-fought election and the heavy Democratic losses had not pushed partisan sparring aside.

“I have no doubt that there will be some Republicans who are angered or frustrated by any executive action that I may take,” Obama said in a post-election news conference. “Those are folks, I just have to say, who are also deeply opposed to immigration reform, in any form, and blocked the House from being able to pass a bipartisan bill.”

He cast his executive actions as an inducement for Republicans to pass their own immigration bill.

“The best way, if folks are serious about getting immigration reform done, is going ahead and passing a bill and getting it to my desk. And then the executive actions that I take go away,” he said.

Republicans led by McConnell pledged to use their newfound majorities to stop him.

“I hope he won’t do that, because I do think it poisons the well for the opportunity to address a very important domestic issue,” McConnell said in Louisville, Kentucky, as he celebrated a victory in his own Senate race and the GOP’s capture of the Senate.

Some on the right said executive action on immigration could even be grounds for impeachment. Several House Republicans said Obama would make it very difficult to cooperate on other issues if he acts on immigration.

“Him moving ahead like that, I think he’s completely tone deaf to what happened last night,” said Rep. Phil Roe, R-Tenn.

But Obama appeared in no mood for waiting. He had already angered Latinos and immigration advocacy groups this fall when he delayed executive action until after the election.

“What I’m not going to do is just wait,” he said. “I think it’s fair to say I’ve shown a lot of patience.”

Immigration advocates made clear that their patience, too, was at an end.

“The election is over. Act boldly to bring relief to the millions facing deportation and family separation,” Janet Murguia, head of National Council of La Raza, said at a news conference Wednesday. “The Hispanic community has waited too long and expects you to fulfill your promise.”

White House officials say Obama, who is traveling to Asia and Australia next week, would not take any action until late November at the earliest and could wait until December.

Advocates in touch with the White House expect Obama to expand a 2-year-old program that deferred deportations for more than 500,000 immigrants brought here illegally as minors, and made them eligible for work permits. He is also expected to take steps to make more business visas available.

Advocates say White House officials are debating whether to require a certain term of residency in the U.S. — say 10 years — and whether eligibility criteria would include the parents of immigrants who received deportation deferrals under Obama, or only people who have children who are U.S. citizens because they were born here.

Such decisions could determine whether the program affects as many as 3 million people or more, or fewer.

In an interview, Rep. Luis Gutierrez, D-Ill., a leading immigration advocate, said anything fewer than 5 million to 8 million people would be insufficient. He and others argue that Obama’s actions will infuriate Republicans no matter how many are affected.

“Half a loaf is going to be unsatisfactory to everyone,” Gutierrez said.

• Politics & Government
• Immigration Issues
• Barack Obama
• immigration reform