and julianna goldman has the results. >> reporter: donald trump has become the republican front-runner because of his reputation as a businessman who gets things done. that brought several lawsuits related to trump university which his lawyer says would extend into a potential trump administration. >> what i was looking for was guidance into how to finance real estate transactions. >> reporter: in 2010, former transit worker gary smith was unemployed and desperate to make money. he saw an ad for trump university and turned to a then brand. >> i thought he was like, you know, kind of a top-notch, guru of sorts. >> reporter: he was a big draw for you? >> definitely. >> reporter: smith spent more than $35,000 on trump university and contacted the attorney general of new york after he heard about its $40 million lawsuit against trump claiming the billionaire defrauded students and made an estimated $5 million. >> i didn't want to put my name on anything having to do with education unless it was going to be the best. >> reporter: trump university began in 2004. in 2007 it started offering l

julianna goldman reports. >> reporter: donald trump called for a database to monitor syrian refugees. >> i do want a database for those people coming in. >> reporter: an attempt to clarify where he stands amid an uproar over last week's seeming endorsement of a mandatory registry for muslims living in >> so here's the story. just to set it clear. i want surveillance of these people. >> reporter: several of trump's rivals have said the idea of a national database to track muslims was a bridge too far. but since the paris attacks many gop presidential hopefuls have contributed to the anti-refugee fervor like john kasich, new hampshire. >> i don't want syrian refugees to come here now because we don't know who they are. >> reporter: that rhetoric has been widely criticized by faith-based groups who lead efforts to resettle refugees, and evangelicals are a key demographic in republican fed for political reasons. >> reporter: linda hartke is the ceo of the lutheran immigration and refugee service. >> i again certainly think those who imagine and would say we should just suend the val of an

here's julianna goldman. >> reporter: with national security concerns rising, donald trump leads the republican pack. retired neurosurgeon ben carson is slipping. and senators ted cruz and marco rubio are gaining ground. >> i'm leading every poll by a lot. it's not even a little bit anymore. >> reporter: in the wake of the paris attacks, at least 2/3 of republican voters in the three early contests say a candidate must agree with them on how to handle isis in order to get their vote. and overwhelming majorities favor sending u.s. ground troops to the middle east to fight the terrorist group. today trump built on his controversial policy resume waterboarding, create a watch list for refugees, and monitor mosques. >> i think waterboarding is peanuts compared to what they do to us. >> reporter: in another new poll, 25% of new hampshire primary voters say trump is best equipped to handle the u.s. response to isis. rubio lags behind with 13%. >> what happened in paris could happen here. >> reporter: the florida senator said his campaign was using the issue for its first campaign ad. >> i