“Republican front-runner Mitt Romney has begun his search for a running mate in the race for president, and he will be guided in part by the lessons his party learned from Sarah Palin's selection four years ago,” AP writes. As he prepares for the chance to challenge President Barack Obama in November, Romney wants to avoid the blowback Republican John McCain faced in 2008 with his surprise choice of the little-known Alaska governor as the vice-presidential candidate. Questions about Palin's readiness to serve and McCain's decision making came to define his flawed campaign. Romney will put experience at the top of his list of qualities as he chooses a No. 2, according to senior advisers and Republican operatives familiar with his thinking.”

Romney tapped longtime aide Beth Myers to head up his vice-presidential search. The Boston Globe profiles her. Romney told ABC he has a deadline in mind for making the pick, but isn’t sharing yet. "It would certainly be by the time of the convention," he said. "I don't think we've chosen the time we'd actually make an announcement."

Romney “denied that the campaign already has a shortlist,” The Hill writes. He said, "I think it's way too early to begin narrowing down who the potential vice presidential nominees might be. But we're beginning that process."

Al Hunt warns: “It’s the time of the political season when conjecture runs wild, much of it ill-informed. Mr. Romney’s choice of a vice-presidential candidate will evolve, in ways unforeseeable today, over the next four months.”

AYOTTE: The New Hampshire senator pens an op-ed in the New Hampshire Union Leader. “April 15 is famous for being ‘tax day,’” she writes. “But this date is significant for another reason — it's also the legal deadline by which Congress is supposed to have approved a budget resolution. Unfortunately, the Democratic-controlled Senate hasn't just missed it this year — the chamber has now gone 1,084 days without passing a spending plan. I ran for the Senate to get America's fiscal house in order. That's why I was so excited to be named to the Budget Committee.” (She touts Ryan’s plan.)

MARTINEZ: It’s looking more and more like New Mexico Gov. Susana Martinez is a non-starter. The Weekly Standard in a profile and interview with her: “Martinez has a simple, one-word answer when I ask if she would consider accepting the vice presidential nomination: ‘No.’ Emphatically no? ‘Emphatically,’ she says. What will she say if Romney calls her in late July to ask her the same question? ‘I am going to say that I am very honored and very humbled but I must decline,’ she says.”

And: “She and Franco are the primary caretakers for her developmentally disabled sister, and Martinez recently told the Albuquerque Journal she ‘just couldn’t’ consider moving her sister to Washington. She’s a little more than a year into her first term, and there’s plenty left to do in Santa Fe: education reform, tax reform, bringing ‘the people to the process’ (a populist trope she repeats often). She’s also no doubt haunted by how New Mexicans perceived the national ambitions of her predecessor, Democrat Bill Richardson, who ran unsuccessfully for president in 2008.”

MCDONNELL: Something to run on… “Gov. Bob McDonnell is promoting legislation that he says will help Virginia become the ‘energy capital of the East Coast,’” AP writes. “McDonnell will add his signature Tuesday to 13 pieces of energy-related legislation. The legislation promotes development of the state’s energy resources and supports alternative and renewable energy strategies, according to the governor’s office.”

RUBIO: Not everyone’s convinced Marco Rubio would be Romney’s Latino answer.

But at least one immigration advocate is warm to Rubio’s DREAM Act.

RYAN: Ryan’s got $5 million in the bank for his reelection bid.

Not every conservative might be happy with Ryan’s plan. But plenty do.