Please help me to understand the following 2 sentences. 1."- Everyone, let's go. Pitches! - Pitches, sir? - Come on, cough them up." Here, what does "pitches" mean？ 2. "The primary-- race is too tight againTo tell a front runner at the 11th hour,So I'm looking at how accurate exit polls are in elections. History of primaries-- what are they? Who selects the candidates?How far they have to tack back to their base before swinging center." "How far they have to tack back to their base before swinging center."what does this sentence mean? and what does "swinging center" mean?