"Dancing With the Stars" drew 18.6 million viewers on Monday, according to Nielsen estimates, helping ABC earn the most viewers for the night over all. But among viewers 18 to 49, the CBS comedy lineup edged ahead, winning the 9 p.m. time slot with "Two and a Half Men" (14.6 million), the night’s top-rated show in that age group. CBS’s "Worst Week" (10 million) was less impressive, while "The Big Bang Theory" (9.3 million) and "How I Met Your Mother" (9.4 million) remained close behind ABC with the 18-to-49 set. CBS dominated the 10 p.m. hour with "CSI: Miami" (13.2 million), which outpaced ABC’s "Boston Legal" (9 million) and NBC’s "My Own Worst Enemy" (5.7 million). NBC ranked third for the night, garnering just 6.7 million viewers for "Chuck" and 8.5 million for "Heroes."