[snip] Interviews with a dozen advisers, including those inside campaigns and those aligned with outside groups, show lines of attack likely to emerge...... While Mr. Romney’s position as an early leader in the race has been shaken by Mr. Perry, it will almost certainly not be Mr. Romney who engages Mr. Perry first. He is already the subject of criticism from other rivals, including former Senator Rick Santorum of Pennsylvania, who questions Mr. Perry’s credentials. “We’ll see how conservative Rick Perry really is,” Mr. Santorum said. Here in Iowa, where the caucuses start the nominating contest, Mr. Perry is placing...