WASHINGTON -- Immigrant youth activists called on leading Senate Democrats Tuesday to demand that President Barack Obama order a halt to most deportations of people living in the U.S. illegally.

Obama, meanwhile, tried to increase pressure on House Republicans to pass immigration legislation that would let most of those 11.5 million people stay in the country.

The developments highlighted a split among Democrats and immigration advocates: Some want immediate executive action by Obama; others say the focus should stay on House Republicans while there’s still a chance, however slim, to pass an immigration bill.

At the White House, Obama addressed law enforcement officers, exhorting them to lobby Speaker John Boehner, R-Ohio, and House Republicans ahead of November midterm elections.

"We’ve got maybe a window of two, three months to get the ball rolling in the House of Representatives. And your voices are going to be absolutely critical to that effort," the president said.

Obama said he believed Boehner wants to get immigration done, blaming "a handful of House Republicans" for inaction 11 months after the Senate passed a far-reaching bill with billions more dollars for border security and a path to citizenship for most of the people in the country illegally.

Not long after the president spoke, several dozen youth immigrant activists gathered in a park near the Capitol wearing blue shirts with the slogan, "Obama Deports Parents!"

They took their demands to the offices of three Senate Democrats -- Harry Reid, Chuck Schumer and Michael Bennet. Reid is the majority leader, and Schumer and Bennet were leaders on the immigration bill. All three instead issued statements demanding the House act.

"If the House continues to drag its feet, we encourage the administration to pursue its efforts to prevent these innocent families from being ripped apart," said Adam Bozzi, a spokesman for Bennet.

Julieta Garibay, a leader of the group United We Dream, which represents immigrants brought to the country illegally as youths, said Democrats cannot continue hiding behind Republicans. "You need to stand with our families," she said.

Obama in March tasked his new Homeland Security secretary, Jeh Johnson, to review how to make deportation policy more humane. Some activists anticipated quick results. When that didn’t happen, divisions began to emerge.

United We Dream emerged among the most outspoken in demanding that Obama act immediately. Obama took such a step in 2012 for some immigrants brought illegally to the U.S. as youths, allowing them to apply for work permits and stay. Now advocates want that program extended to parents of those youths as well as to parents of children born in the U.S.

Others have urged the administration to wait at least until Congress’ August recess. Boehner and other House Republicans have warned that executive action by Obama would increase distrust among House Republicans and ruin chances for bipartisan cooperation on immigration.

A top Schumer aide, Leon Fresco, expressed this view to White House adviser Cecilia Munoz in a recent meeting. Schumer declined to comment Tuesday but his spokesman, Matt House, said, "We recognize that our broken immigration system is causing a great deal of frustration in our community. But now is the time to pressure Republicans to act."

Disputes among advocates over tactics may be producing unintended consequences.

Sen. Bob Menendez, D-N.J., praised by advocacy groups because he called on the administration in March to "take action today" to ease deportations, stepped back from that position in an interview Tuesday with The Associated Press.

"What I think should happen now is that we should be focusing our attention on the House in what I think is the last window of opportunity to get what I think can be a bipartisan and comprehensive reform," Menendez said. "And when we’ve exhausted that, if that ends up being the case that there is no opportunity in the House, then I will return to my calls for presidential use of his executive powers."