Thomson ReutersJanuary 29, 2013 11:00
* Obama, Republicans differ on border security
* Immigration suddenly a priority in Washington
* US has 11 million illegal immigrants
* Obama launches immigration reform in Las Vegas (Adds more details)
By Matt Spetalnick
LAS VEGAS, Jan 29 (Reuters) - Just over a week into his second term, President Barack Obama took his fight for immigration reform to the West on Tuesday and pushed Congress to quickly find a path to citizenship for 11 million undocumented residents.