STAFFORD, Va. — Just outside the gates of the storied Quantico Marine Base, George Allen, the Republican nominee for a Senate seat from Virginia, sat down in the offices of a moving van company with more than a dozen defense contractors from his state last Monday to listen to them fret over government spending cuts.

Scott Hirons’s small software firm will probably have to shrink to five employees from 15 by the end of October if nothing is done to head off automatic, across-the-board defense cuts, he said. The cuts will not begin until January, if ever, but the threat alone has already frozen the contracting world, Mr. Hirons said. John Radziszewski worried not just about spending cuts but also about the Pentagon’s recent moves to “in-source” work to government research labs to save money.

“I personally could never imagine voting for something so devastating to our national security and jobs in Virginia,” said Mr. Allen, a former senator seeking to regain the seat he lost six years ago to Jim Webb, a Democrat, who is retiring.

In an election year when the Republican Party has set itself up as a paragon of small government and the scourge of federal debt, Mr. Allen is taking a different tack. He has made opposition to the bipartisan deficit reduction law of 2011 the centerpiece of his campaign. In Virginia, home to thousands of defense contractors ringing the Pentagon and vast military bases around Norfolk, Mr. Allen is seen as the Old Dominion’s version of Senator Pothole — as former Senator Alfonse M. D’Amato, Republican of New York, was known for his attention to local issues.