A Turn to Trusted Aides for Quick Responses The most important voice in a presidential campaign is that of the candidate. But it is not the only important voice, as President Obama and Mitt Romney recently acknowledged. In the last two weeks, both campaigns have had close advisers increase their day-to-day communications with reporters and various media outlets. It is a recognition that they cannot afford to miss a beat in a rapid-fire media environment fueled by Twitter and cable news programs. The additions of the high-profile representatives signal that the campaign is moving into a new phase in which speed in responding is essential. Jennifer Psaki, a former deputy communications director in Mr. Obama's White House, will join him on the trail, reprising a role she had in 2008. Kevin Madden, already a senior adviser to Mr. Romney, will become a more frequent traveler and spokesman as he was in the campaign for the 2008 Republican nomination. They will each face the following challenges: MS. PSAKI Campaigning for re-election to the White House requires a delicate balance of the official and the political. When Mr. Obama has been on the road, his team has handled communications from afar, with reporters being directed to the campaign's Chicago headquarters. Ms. Psaki's return will change that. Officials said she would work with the White House press secretary, Jay Carney, on most political trips, serving as the official voice of the campaign for the gaggle of reporters who accompany the president wherever he goes. Ms. Psaki faces the challenge of putting the best possible face on a tricky re-election message. How to signal that things are getting better when the unemployment rate is hovering above 8 percent? Mr. Obama's recent stumble when he said the private sector was "doing fine" would have put her on the spot. Friday's mediocre jobs report offered the latest dangerous moment that demanded a nimble response. There is no shortage of people who speak for Mr. Obama's campaign. Frequent guests on television programs include David Axelrod, the senior adviser; Stephanie Cutter, the deputy campaign manager; and Robert Gibbs, the former White House press secretary. But Ms. Psaki will often be first to respond. Vivacious and well liked by the news media, she also has the respect of the president, who nearly offered her the press secretary job after Mr. Gibbs left last year. This week, Mr. Obama will travel to Iowa and Virginia, two swing states where the economy is doing better than the rest of the nation. Expect to see Ms. Psaki remind reporters of that fact frequently as the president makes the case to voters that his policies are working, even if it is more slowly than people want. MR. MADDEN The challenge for Mr. Romney is to find a way to maintain the focus of his campaign despite the distractions that can sometimes knock a candidate off message. Mr. Madden's arrival is part of that effort. The fight over the health care law is a good example. When the Supreme Court issued its ruling upholding the law, Mr. Romney's campaign got tripped up twice - first when a press aide was put on camera, and later when a senior adviser contradicted the message of other Republican officials by saying Mr. Obama's health care mandate was not a tax. Mr. Madden, whose relationship with Mr. Romney goes back years, might have been able to help in both cases. As a traveling spokesman, Mr. Madden will become the first senior-level communicator to travel with the candidate since the 2012 campaign began. Like Ms. Psaki, Mr. Madden is well known and well liked by the press and has deep ties to Mr. Romney's senior campaign staff members and the Republican leadership. He served as press secretary for Speaker John A. Boehner when Republicans were in the minority in the House. He also brags about having perfect hair for television. His skills will be put to the test this week. On Wednesday, Mr. Romney will give a speech to the N.A.A.C.P., a sensitive venue for a Republican presidential candidate running against the first black president. Also this week, Mr. Boehner plans to push forward with a House vote to repeal Mr. Obama's health care law. The effort will not succeed in the Democratic-controlled Senate, but it could serve once again to distract from Mr. Romney's focus on the economy.