President Obama believes a new immigration bill can be passed by June, but two leading political figures in immigration reform warned that Congress faces a "tough slog" to pass the new bill.

“I’m hopeful that this can get done, and I don’t think that it should take many, many months,” Obama said in an interview with Telemundo. “I think this is something we should be able to get done certainly this year and I’d like to see if we could get it done sooner, in the first half of the year if possible.”

Chuck Schumer and John McCain, two members of the bipartisan Senate group that crafted immigration reform proposals, predicted that reform will garner support from both Democrats and Republicans — and pass the Senate and then the House.

“I think it could take three, four weeks,” Schumer said Wednesday at an event, referring to the length of debate in the Senate alone when it finally comes up,The Hill reports.

“This is such an important issue to America, and it's so complicated, and it deals with every aspect, that I think we should have a full and robust debate. And by the way, the hope is that we could pass this with a nice, sizable, bipartisan majority. Because that could set the stage — make it easier for the House to pass it.”

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"We don't want to have just four, five Republicans," Schumer added.

Former GOP presidential candidate John McCain pointed out "there won't be" only a small number of Senate Republicans supporting the bill.

"It's going to be a tough slog," McCain added. "It's going to be a tough, tough fight."

“I think probably one of the scenarios is a majority of the Democrats in the House and maybe a majority of the Republicans in the House," McCain said. "I would not anticipate a unanimous Republican support, but I think there can be significant Republican support.”

On Tuesday in Las Vegas President Obama unveiled his plan for tackling immigration reform.

Both the president’s and Senate plan seek to create a path to citizenship for an estimated 11 million illegal immigrants already in the country.

McCain said that if Republicans do not pass immigration reform, the loss of Hispanic voters will continue to hurt the party.

“I think the trend will continue of lack of support from Hispanic voters, and also as you look at the demographics of states like mine — that means we will go from Republican to Democrat over time,” McCain said.

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Meanwhile, Joe Crowley, the Vice Chair of the House Democratic Caucus, praised President Obama’s reform proposal.

““I applaud President Obama for advancing the dialogue on immigration reform and calling for a real, meaningful solution that meets the challenges of our broken immigration system.

“As the son and grandson of Irish immigrants, my family’s story is not unlike that of millions of Americans across our great country. We are a nation built by immigrants, and we are stronger because of it. But our current system is not meeting our country’s needs, putting this proud tradition at risk.”

Read more: Immigration reform advocate Chuck Schumer says 2013 year Congress ‘finally gets it done’

President Barack ObamaAP