The House Democrats’ campaign arm on Monday added Jessica Killin to its nationwide “Red to Blue” program in Colorado’s Republican-leaning 5th Congressional District, calling the first-time candidate a “top-tier” challenger in a seat the party is aiming to flip in this year’s midterm elections. Killin, an Army veteran and former chief of staff to second gentleman Doug Emhoff, is facing fellow veteran and nonprofit leader Joe Reagan in the June primary for the chance to take on Colorado Springs Republican U.S. Rep. Jeff Crank, a former podcaster and longtime political operative serving his first term. Killin was one of eight new candidates added this week to the Democratic Congressional Campaign Committee’s program, which provides advice, fundraising and staff support to candidates whose campaigns have met organizational and financial benchmarks, the group said. U.S. Rep.…