by ANDREW RAFFERTY and ALEX STAMBAUGH
Republican presidential candidate Ben Carson knocked rival Donald Trump's immigration plan on Tuesday, saying that deporting the country's undocumented immigrants "sounds really cool" but would be far too costly and complicated.
"It sounds really cool, you know, 'Let's just round them all up and send them back,'" Carson said. "People who say that have no idea what that would entail in terms of our legal system, the costs - forget about it. Plus, where you gonna send them? It's just a double whammy."
Carson has been gaining on Trump, the GOP frontrunner, in recent polls. An NBC/Marist poll released Sunday found Carson has jumped to second place in Iowa among Republican voters, seven points behind the real estate mogul.
Trump's immigration plan calls for deporting the estimated 11 million undocumented workers currently in the U.S., a proposal that opponents say would cost billions and would be nearly impossible to execute. Carson said that he instead favors a plan that would allow undocumented workers the chance to become guest workers.
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The outspoken leader of the GOP field has so far refrained from knocking Carson, though that could soon change if the former neurosurgeon continues his steady rise in the polls.
"I'm hoping for Ben to really hit me at some point because I love to counter-punch," Trump said on MSNBC's "Morning Joe" last week.
During Caron's discussion at the Commonwealth Club of San Francisco on Tuesday, he also said he believes God is "opening doors" for his campaign.
"I just said, Lord, you know it's not something that I particularly wish to do," Carson said of a 2016 run. "But if you really want me to do it, you'll have to open the doors because all the pundits and all the experts say it's impossible for someone like me to put together a national organization to be able to raise adequate funds, to do all the things that are necessary."
"I have no great ambition quite frankly to do this, but I feel called to do it by a lot of my fellow Americans and the doors are opening," he added.