When the Great Recession began in December 2007, Maryland and Virginia had identical 3.3 percent unemployment rates. Fifty-seven months later, the employment situations in these two similar states couldn't be more different.

Virginia's unemployment rate reached a high of 7.3 percent in January 2010, and has since declined to just 5.9 percent. In Maryland, unemployment reached 8 percent in that same month and has remained stubbornly high at 7.1 percent.

What does all this have to do with the U.S. Senate race between former Virginia Govs. Tim Kaine and George Allen? Everything. Virginia has succeeded economically where Maryland has failed, because the commonwealth has the freedom to pursue pro-growth policies at the state level. The Obama agenda, for which Kaine never fails to serve as a rubber stamp, threatens Virginia's ability to differentiate itself from Maryland.

Take Obama's signature domestic initiative, which Kaine supported wholeheartedly: Obamacare. According to the Kaiser Family Foundation, Virginia's government spends just $6,286 per resident on health care, almost $600 below the national average. Maryland spends $7,492 per resident on health care, more than $600 above the national average. With Obamacare's Medicaid expansion, that $1,200 per person spending gap will have to be made up somewhere. Where? Through higher taxes, and perhaps also through higher costs to the state's private employers.

A big reason why both CNBC and Chief Executive Magazine ranked Virginia in the top 10 states to do business was its low tax burden. By contrast, a big reason Maryland finished in the bottom of both state business rankings is that its tax burden is so high.

Obamacare will force Virginia to spend far more on health care than it does today. That extra money will have to come from either higher taxes, lower education spending or lower infrastructure spending. Is that really a decision Virginians want the federal government to force them to make?

Kaine has a long history of favoring the Democratic Party's best interests over those of Virginia. His decision as governor to hand over the Virginia-owned Dulles Toll Road to the Democrat-controlled Metropolitan Washington Airports Authority, or MWAA, was supposed to ensure a better-managed, more cost-effective Dulles Rail project. The MWAA rewarded the state by adopting a pro-union project labor agreement that discriminated against all Virginia contractors. The MWAA has also been plagued by ethical lapses and scandals that Marylanders and D.C. residents have come to expect from their politicians. Thanks to Kaine and his Democratic cronies, Dulles Toll Road commuters are now facing steeply escalating tolls that will reach as high as $10 one way by 2020.

The contrast between Kaine's partisan sellouts and Allen's common-sense conservatism could not be greater. Where Kaine has defended every aspect of Obama's disastrous green energy agenda, Allen has based his campaign on a prudent energy plan that will allow Virginia to keep taxes low, responsibly develop the state's energy resources and fund much-needed infrastructure projects.

Virginians face a stark choice this November at the polls: They can vote for Kaine and take another step toward becoming a carbon copy of high-tax, high-unemployment Maryland; or they can vote for Allen and continue Virginia's well-deserved economic success.