Just a few days before the first presidential debate, surrogates from both campaigns will join the Sunday talk shows to weigh in on what Mitt Romney and President Obama need to do to reach voters. Representative Paul D. Ryan of Wisconsin will grant an exclusive interview to "Fox News Sunday." Gov. Chris Christie of New Jersey makes the rounds on behalf of Team Romney, appearing on ABC's "This Week," CBS's "Face the Nation" and NBC's "Meet the Press." David Plouffe, a White House adviser, will also appear on ABC and NBC, discussing Wednesday's debate in Denver and Mr. Obama's recent gains in polls in key battleground states. On ABC, the political roundtable will feature Haley Barbour, the chairman of the Republican National Committee and a former Mississippi governor, and Howard Dean, a former Vermont governor and a former chairman of the Democratic National Committee. NBC's roundtable will include Ralph Reed, the founder of the Faith and Freedom Coalition, and Ed Rendell, the former Pennsylvania governor. Newt Gingrich, a former House speaker and presidential candidate, will join Mr. Christie on CBS, discussing how the Romney campaign can win over voters. Also, Representative Marsha Blackburn, Republican of Tennessee, will appear on the roundtable. Senator John McCain of Arizona, a former Republican presidential nominee, will be on CNN's "State of the Union" to talk about the debate from a unique perspective: that of someone who has debated both candidates in the past. He will also weigh in on recent foreign policy developments in Libya and Syria. Also on CNN: David Axelrod, an adviser to Mr. Obama's re-election campaign, talking about the home stretch of the race. Plus, Senator Roy Blunt, Republican of Missouri, and Gov. Martin O'Malley of Maryland, the chairman of the Democratic Governors Association, discuss what voters want to hear from the candidates. Senator Richard G. Lugar of Indiana, the ranking Republican on the Senate Foreign Relations Committee, is on Bloomberg's "Political Capital." Housing Secretary Shaun Donovan discusses the state of the housing market on C-Span's "Newsmakers." TV One's "Washington Watch" includes conversations about the presidential race and an interview with Colin L. Powell, the retired general and former secretary of state. Otto Pérez Molina, the president of Guatemala, and Juan Manuel Santos, the president of Colombia, will appear on Univision's "Al Punto," as will surrogates from the Romney and Obama campaigns. The president of Guatemala will also be on Telemundo's "Enfoque," along with Otto J. Reich, a former U.S. ambassador to Venezuela.