[...] immigration critics waged a public campaign against McCaul in recent days, recalling his past support of proposals that included a path to citizenship for undocumented immigrants. Kelly's selection drew praise from immigration critics while pro-immigration advocates said they were hopeful that Kelly's experience in Central America could foster a better understanding in the Trump administration of causes of migration. [...] the Federation for American Immigration Reform, which has been strongly critical of Obama administration policies, said Kelly would bring "an unwavering commitment" to protecting the border. Federation president Dan Stein said in a statement that Kelly "fully understands the critical role border security plays in protecting the country from the threats of terrorism, uncontrolled illegal immigration, and drugs." Pro-immigration groups were alarmed by Trump's choice of Alabama Republican Sen. Jeff Sessions as attorney general and they feared that Trump might pick Kansas Secretary of State Kris Kobach, a noted immigration hawk, to lead Homeland Security. Frank Sharry, founder of America's Voice, an alliance of pro-immigration groups, said he was intrigued by Kelly's involvement in combating gang violence and problems in El Salvador and other Central American nations from which people are fleeing northward.