Washington (CNN) - Rick Santorum and Mitt Romney are likely to meet in early May to discuss a Santorum endorsement, his role as a Romney surrogate and conservative policy issues, CNN has learned. John Brabender, a senior strategist for the Santorum campaign, told CNN that Santorum's goal is to have a policy-oriented session in which he tries to find a "comfort level" about the role "social conservatives, tea party activists and blue collar Republicans will play in the campaign and in the Romney administration." Even so, he said, "we are not walking in there with a litmus test. This is...