If conservatives win a primary, they can not go on to win a general election according to the Washington Post’s Tim Craig. In his post primary analysis, Craig cited two primary victories for conservative Republicans, and spun it as "troubling signs for the [Republican] party."
The two defeated incumbent moderates include Martin E. Williams of Newport News and J. Brandon Bell II of Roanoke. In fairness, it is defensible to suggest a moderate Republican would fare better in Newport News (John Kerry narrowly carried the city in 2004). However, George W. Bush carried Roanoke by 30 points that same year, and it would be ridiculous to suggest a conservative can not prevail there.
Craig painted a very grim future for Republicans asserting that "Democrats and even some Republicans say the conservatives might regret their decisions come November 6." Craig then sought to hype up division within the Republican party quoting retiring moderate GOP Senator H. Russell Potts with the threat: "If Republicans retain control of the Senate, it will be almost as far right and radical as the House of Delegates and that’s bad news for Virginia."
In Tim Craig’s world, Republicans can only win, even in "deep red" communities of Virginia, if they abandon conservative principles.