House Majority Whip Tom Emmer speaks at the Republicans' Dallas convention in September. (Julio Cortez/AP)McALLEN, Texas — Despite the headwinds across the country, House Republicans feel bullish about their chances to expand their grip in what’s been a solidly red state, thanks to midcycle redistricting.Roughly a month before the midterms, House Majority Whip Tom Emmer traveled to the southwest border and gathered nine of the GOP’s top recruits…