By Richard Cowan
WASHINGTON (Reuters) - Senate Republicans on Tuesday turned up the heat on Democrats to accept demands from President Donald Trump for tougher immigration laws and a wall on the U.S.-Mexico border as part of a bipartisan deal to aid young "Dreamer" immigrants.
Senate Majority Leader Mitch McConnell, a Republican, backed legislation to encompass Trump's "four pillars" of immigration reform, which include plans to build the wall, end the visa lottery program and impose curbs on visas for the families of legal immigrants.
"This proposal has my support and during this week of fair debate I believe it deserves support of every senator who's ready to move beyond making points and actually making a law," McConnell, said in a speech on the Senate floor.
The Trump "pillar" of immigration that is easiest for Democrats to accept is protecting some 1.8 million Dreamers who were brought illegally to the United States as children. Many Democrats are reluctant to help fund the wall, which is aimed at keeping illegal immigrants out but is seen by many lawmakers as too expensive and too inefficient.
The U.S. Senate began a major immigration debate, its first in nearly five years, on Monday evening. Republicans held a tough line, at least for now, in the search for a bipartisan deal.
Republican Senator Tom Cotton, interviewed on Fox News, said Trump's immigration plan "is not an opening bid for negotiations. It's a best and final offer."
But that ran counter to statements Trump has made in recent days, including early on Tuesday in which he said in a tweet that "Negotiations on DACA have begun," suggesting that he sees room to budge on some issues.
Congress has been trying and failing to pass a comprehensive immigration bill for more than a decade, most recently in 2013 when the Senate voted to grant a pathway to U.S. citizenship for millions of illegal immigrants. That effort later died in the House of Representatives.
Some Republican lawmakers have expressed skepticism that the kind of broad fundamental changes in U.S. immigration law sought by Trump can pass the Senate in the coming days, as Republican leaders plan.
The administration proposes cracking down on overall levels of legal immigration and the type of immigrants who would qualify for visas. Trump wants to aim U.S. immigrant visas at high-skilled workers and allow fewer relatives of legal immigrants.
Standing beside a large photograph of American snowboarder Chloe Kim, who at 17 became the youngest female snowboarder to win an Olympic gold medal, Democratic Senator Dick Durbin said, “Some say there are too many immigrants.” He added that Kim is “the daughter of an immigrant who came here with nothing.”
Her father, Kim Jong-jin, is a South Korean immigrant who gave up his job as an engineer to focus on his daughter's budding sporting career.
Durbin told reporters he thought early Senate votes on immigration proposals from both sides could fail to win the 60 votes needed to clear procedural hurdles.
Then, Durbin said, senators will be forced to move "toward the center with a moderate approach."
The Senate was spending much of Tuesday treading water as behind-the-scenes negotiations continued.
DACA is the Deferred Action for Childhood Arrivals program, which Democratic former President Barack Obama initiated in 2012 and which has allowed around 700,000 Dreamers to legally study and work in the United States temporarily. Last September, Trump announced he would terminate the program on March 5.
Democrats have talked of the possibility of providing a pathway to citizenship for Dreamers and additional border security, including the construction of more border fencing and other high-tech tools to deter illegal immigrants.
A group that includes several centrist senators was working on a proposal which likely would include around $25 billion in additional money for border security, said Democratic Senator Bill Nelson.
While Trump would want to focus that money on construction of a U.S.-Mexico border wall, Nelson said, “A wall is many things.” He said it could include electronic devices, natural boundaries and drones.
(Reporting By Richard Cowan, additional reporting by Katanga Johnson and Susan Cornwell; Writing by Alistair Bell; Editing by Bernadette Baum and Jonathan Oatis)