Rep. Joe Sestak, the Democratic nominee in the Pennsylvania Senate race, disclosed Thursday that White House officials contacted his brother in preparation for a response to allegations that Sestak was offered a job in the Obama administration as an enticement not to challenge incumbent Sen. Arlen Specter. Faced with mounting scrutiny from Capitol Hill and accusations that such an offer might violate the law, President Barack Obama promised Thursday to have "an official response shortly on the Sestak issue." Sestak said in a television interview in February that the White House had offered him a top job in the administration to try to dissuade him from challenging Specter in Pennsylvania's May 18 Democratic primary, which Sestak won. Sestak, a former Navy admiral, has refused to identify the job, but there has been speculation it could have been secretary of the Navy. He predicted that a White House announcement was imminent, although he made several references to Friday. "I think shortly should mean shortly," he said. "At least, in the Navy, that means" — Sestak snapped his fingers — "you know what I mean, like this." He told reporters that the White House had contacted his brother and campaign director, Richard Sestak, on his cell phone Wednesday. He said the White House got his brother's number through an unnamed third party. Sestak said his brother and an unnamed White House official or officials spoke about "what was going to occur." Sestak declined to identify who made the call for the administration, adding that he has had no direct contact with the White House. Sestak called Obama a "pretty legitimate person." He added, "But we'll find out shortly what they have to say." Sestak was tight-lipped about the situation, declining to comment on whether he would agree with the White House's take on the situation. He pledged to say more — and even to return to Washington for a Capitol Hill news conference over the weekend or early next week — once the White House had made its announcement. "When the president speaks — or whoever speaks from the White House — we obviously will have something to say," he said. He defended his own disclosure in the interview and disputed the notion that the controversy would affect his race. "I made sure I talked about my role in this and what I felt was right," Sestak said. "I answered honestly." Jen Bendery contributed to this report.