Obama's magic number is 40

The consensus among political pundits is that Republicans have around a 60-percent chance of gaining control of the Senate in this fall's midterm elections. However, this projection erroneously assumes that the GOP has already nationalized the slate of competitive races by tying vulnerable Senate Democratic incumbents to President Obama like a lead weight. In reality, polling thus far shows that voters in the battleground states are focused on their respective local elections rather than casting a protest vote against Obama. And for that dynamic to change, it will likely take an event as disastrous as the failed Obamacare rollout.

President Barack Obama
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President Barack Obama

Political forecasters are prone to develop comparisons between the current and past election cycles, using the president's approval rating as a key harbinger for things to come, even though Obama is not on the ballot. But recent trends are more important indicators than comparisons to the electoral environment four, eight, or 80 years ago, particularly as the country has become more polarized.

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So, when pundits harp on Obama's poor approval ratings, the first question should be "relative to what?" Sure, there are similarities to George W. Bush and contrasts to Bill Clinton that can be made relative to this point in their presidential terms, but voters aren't the ones conducting that analysis. Instead, voters tend to have short memories and attention spans, gauging their approval of politicians' performance on the principle of "what have you done for me lately." A typical voter's default position is to focus on the particular choice in front of them — whether to support their current senator or back his or her challenger — rather than register a protest vote against the president, unless they have so soured on him that the local races have largely nationalized.

So far, the polling data in the Senate battleground states does not show signs of nationalization. Take, for example, one of the most vulnerable Democratic incumbents, North Carolina's Kay Hagan. The GOP does not even have to do any work to link Hagan to Obama, she has done it for them by embracing his signature health-care reform initiative from day one. Hagan swept into office on the coattails of Obama six years ago, but is now struggling with her own low approval rating in a state that has experienced a clear shift to the right during her tenure. Yet Hagan is still locked in a statistical dead heat with her challenger, state House Speaker Thom Tillis, thanks to his own approval rating, which is even more dismal than Hagan's. If voters in the Tar Heel State were focused on sending a message to Obama, they wouldn't care who Hagan's challenger was. They would be willing to vote for a toy monkey banging cymbals as long as it was not a Democrat. In fact, a third party Libertarian candidate appears to be stealing more votes from Tillis than Hagan — third-party candidates are another traditional repository of protest votes, but their support usually dissipates as election day draws near.

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For another case in point, go inside the numbers in Arkansas. Democratic incumbent Mark Pryor was widely considered to be a dead man walking at the beginning of this election cycle. And the GOP fielded one of their strongest candidates on paper, Rep. Tom Cotton, who attended Harvard for both undergraduate and law school, served as a platoon leader in the 101st Airborne during combat in Iraq, and deployed twice to Afghanistan. Yet despite Obama registering an approval rating in the Natural State almost 10 points below his national average, Pryor and Cotton remain neck and neck. And Pryor recently ran a campaign ad highlighting his support for Obamacare — not the move that a candidate who fears being tied to the president would likely make.

Think of Obama's approval rating as a stock quote with the ticker symbol "O44" (Obama being the 44th president). According to the RealClearPolitics average, O44 has been trading in a narrow band between 40 and 45 for more than the past year. It has a technical support level at 40, which it only briefly tested on December 3, 2013, at the nadir of the catastrophic launch of the Healthcare.gov website.

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For Obama's approval rating to drop enough before election day to nationalize this year's Senate races, it is going to have to descend into uncharted territory below its stubborn 40 percent support level. But for that to occur, Obama will have to suffer a negative catalyst on the magnitude of the failed Obamacare rollout within the next two months. Otherwise, for the Republicans to win control of the Senate, they will need to wrest at least six seats net in hand to hand combat from the actual Democratic senators who hold them rather than buying into the mistaken consensus that they have the option of simply running against Obama.

Commentary by Stephen A. Myrow, managing partner of Beacon Policy Advisors LLC, an independent policy research firm based in Washington, DC. He served as Chief of Staff to Deputy Secretary of the Treasury Robert M. Kimmitt in 2008-2009. Follow him on Twitter @smyrow.