Sen. Mark Warner (D-Va.) is in a lot more trouble than it seems. Despite his ample war chest and approval ratings, only 50 percent of Virginians say Warner should get a second term. And independents, by a margin of 49 to 43 percent, say they would rather have someone new in Virginia’s Senate seat.

Moreover, Warner will have to defend his deciding vote for Obamacare during a midterm election that will likely be driven by voter anger over Obamacare. Virginians upset about President Obama’s false promise that “If you like your health plan, you can keep your health plan” will be surprised to discover that Warner made the same false pledge, declaring “I’m not going to support a health-care reform plan that’s going to take away the health care you’ve got right now or a health-care plan that you like.” He did. And if The Post is right that a second wave of Obamacare-driven cancellations is coming in October, just a few weeks before Election Day, that broken promise will be front and center in voters’ minds when Virginians go to the polls.

Still, in the absence of a skilled, well-funded opponent capable of exploiting these vulnerabilities, Warner might well coast to reelection. But Warner could soon have a credible challenger if Ed Gillespie enters the race — possibly as early as this week.

Like Obama, Warner will try to shift conversation from Obamacare to income inequality. Gillespie won’t let Warner off the hook on Obamacare, but he’s more than ready to engage Warner on the economic debate — and is uniquely positioned to do so. He grew up in a blue-collar family, the son of an immigrant who came here from Ireland when his father found work in America as a janitor. His parents ran a corner grocery store where Gillespie worked as a kid. He was among the first generation in his family to go to college and helped pay his way by working as a U.S. Senate parking lot attendant.

Gillespie will argue that the Obama-Warner economic policies — with $1 trillion in new taxes and $7 trillion in new debt — have put the American Dream out of reach for too many citizens. Virginians’ share of the national debt is rising while incomes are falling. He will reject the idea that this is the new normal and argue that “we can do better,” campaigning on a hopeful message of economic opportunity, upward mobility and helping people rise as far as their hard work and ambition will take them.

Warner will counter by trying to paint Gillespie as a lobbyist and Washington insider, but that will be hard considering Warner’s support last year for Terry McAuliffe — a lobbyist and Washington insider. While Gillespie certainly knows his way around Washington, his heart has always been in state politics. He is unusual in having gone from serving as Republican national chairman to state party chairman, and not the other way around. After leaving the Bush administration, Gillespie founded the Republican State Leadership Committee, a group dedicated to electing Republicans to state office. He raised $50 million for GOP candidates that helped fuel the GOP’s stunning 606-seat gain in state legislatures since Obama took office. Gillespie will have strong grassroots support and no problem raising the resources to make sure every Virginian knows that Warner’s moderate image is a myth.

Some have suggested that, as a former Bush official, Gillespie may not be seen as sufficiently conservative to satisfy the tea party activists and social conservatives who dominate the Virginia Republican Party. They are mistaken.

I worked closely with Gillespie in the White House, and he was a forceful champion for conservative policies in the Bush administration. When some White House advisers tried to get President Bush to support cap and trade, Gillespie stopped it cold. He opposed the auto bailout. On his advice, Bush awarded the Presidential Medal of Freedom to Henry Hyde for his years of service to the pro-life cause, invited March for Life participants to the White House and spoke to the Conservative Political Action Conference for the first time.

He’s a principled and courageous conservative who in his heart is still that blue-collar kid stocking grocery shelves, parking cars and dreaming the American Dream. If elected, Ed Gillespie will become the first person in history to go from the Senate parking lot to the Senate floor. That’s a compelling story — and one that should make Mark Warner very nervous indeed.

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