Ted Johnson NBC will air an hour in primetime of each evening of the Democratic and Republican conventions, in line with previous cycles and other broadcast networks, while MSNBC plans seven hours each night of the events.Lester Holt and Savannah Guthrie will anchor from the network’s headquarters in New York, with Chuck Todd and Andrea Mitchell at the NBC News Washington bureau. The DNC starts on Monday and runs for four nights; the RNC begins on Aug.