President Obama’s congressional charm offensive is set to continue next week when he is joined by his former rival, Rep. Paul Ryan, for a private lunch at the White House. Obama invited Mitt Romney’s former running mate to be his lunch date as part of a renewed effort to break a stalemate on budget negotiations by reaching out to rank-and-file GOP members. Ryan, who wrote the House Republican budget, is working on a plan he claims will eliminate the debt without raising taxes. Obama has insisted that any budget deal include a tax hike on upper-income Americans.