Newt Gingrich labeled rival Mitt Romney ‘Obama-lite’ yesterday, as the two candidates made their closing arguments before today’s Republican presidential caucuses in the key general election battleground of Nevada. “Obama is big food stamp; he is little food stamp,’’ Gingrich told a crowd of several hundred inside a country music club just south of the Las Vegas Strip. Romney, who held a business roundtable discussion earlier in the day, did not directly respond to Gingrich. Instead, he kept his focus on Obama.