Probably the most impressive part of the Democratic and liberal strategy to become dominant in Colorado was its state legislative effort: recruitment, candidate guidance and funding.
The Republican “wave” of 2010 helped them win the House by one seat, but Democrats won it back plus four more in the 2012 Obama presidential win.
Democrats have leveraged pure campaign skill and massive amounts of money to fight well above their natural strength in the Colorado electorate. In 2014, Republicans will have some national advantages to level the playing field a bit. But, they will still have to win it seat by seat.