Mitt Romney is on a roll, winning five Republican presidential contests in a row. Readers differ on the reason for his success.

FoothillWebDesign attributes it to focus, writing in part: “Romney’s been successful by staying on message.The other candidates went after low-hanging fruit. Gingrich’s comments about Romney’s wealth and Santorum’s comments on just about everything were not well-scripted. Romney’s shown faith in the system by being patient, and it’s paying off.”

Others like JMHanes point to his lackluster opponents:

The ideological fickleness of these putative conservatives has been astonishing — whether it’s abandoning the suddenly tongue-tied Perry, or pulling for on-the-job-trainee Herman Cain, whose ignorance of the most basic international players in this crisis-fraught world would make even Obama look like a foreign policy guru. Or Gingrich, who has switched more positions, in faster succession, than Romney ever has, attacking capitalism from the left, and now Santorum, who owed his short Pennsylvania career to wooing unions, barreling pork and growing big gov. The Real Clear Politics average is a chart of serial implosions in contenders who, unlike Mitt, have virtually no reliable base at all to sustain them. The more exposure Santorum gets, the more he looks to track that trend line, although being the last not-Mitt man standing may serve him a little longer.

And some like Jafco point to his improved message: “Romney has always focussed on Obama, and his stump speech and delivery seems to have taken a quantum upward step. Some pundit I read the other day termed Romney ‘a learning machine.’ ”

TheStatistQuo I think, hits the nail on the head:

Santorum’s stumbles are the main reason for Romney’s success. [Santorum] seems to have a compunction to promise he’ll not talk about social issues, just before he starts talking social issues. Because he puts the economy (stupid) on the back burner, he opens the door wide open for Romney to talk about nothing else. The opposite side of the coin of Santorum stumbles is Romney’s economic plan. It may not have received the attention from the gotcha media, but enough voters noticed it to run away from Rick as quickly as possible.

Romney’s team understood from the get-go that if the main topic of the campaign was the economy and not health care he’d win the nomination. It’s also a truism that it helps to have run before. Romney brought into the race 2008 supporters (especially in Iowa), a more relaxed demeanor, debate proficiency and an appreciation for how difficult and wearing the race is. But more than anything else, a campaign over many months in many states requires the very skills and qualities that he possesses: emotional balance, executive planning, budgeting, and compiling and managing a team. People don’t necessarily vote for a candidate because of those qualities, but those characteristics are essential in presidential politics. Oh, and it helps to have a really great spouse.