Correction: An earlier version of this column incorrectly described George Allen, a former Virginia governor and former U.S. senator, as a lobbyist. Allen, who is again running for the Senate, is a political consultant. This version has been corrected.

Prepare for the greenest campaign Virginia has ever seen.

No, former senator George Allen (R) and former governor Tim Kaine (D) won’t likely be tooling around in Priuses as they try to claim the Senate seat being vacated by James Webb (D). They will be instead be battling atop mountains of campaign cash as combatants in what is almost certain to become the most expensive campaign in the commonwealth’s history.

“It’s going to be a lot of outside interests and outside money. It probably will be the most expensive we’ve had,” said Robert E. Denton Jr., a political scientist at Virginia Tech. “It’s going to be a real marquee kind of race.”

Put another way: This election year “is sort of a TV sales rep’s fantasy,” said a consultant involved in the race.

Nineteen months ahead of the actual showdown, anything to be said about the race at this point is little more than rank speculation. But the previous champeens — the $36.9 million spent by Webb and Allen and their parties in 2006 and the $41 million spent on the 2009 general election by Republican Robert Mc­Don­nell and Democrat Creigh Deeds — stand to be left in the dust.

What will be driving much of the spending is the key battleground in the race: the violet-shaded outside-the-Beltway communities of Northern Virginia that sent Kaine to the Executive Mansion in 2005 and then picked McDonnell to replace him four years later are going to get a whole lot of attention from both candidates. Those households happen to reside within a Top 10 national media market, one where it could cost $1 million a week to wage an effective broadcast effort next fall. Additional cash will be spent on somewhat cheaper advertising in Hampton Roads, Richmond and Roanoke.

There is little doubt there will be money to spend.

Start with the candidates themselves. Both are accomplished fundraisers plugged into national donor networks: Kaine is the immediate past chairman of the Democratic National Committee, leading one senior Allen adviser to conclude that “George Allen is going to be outspent.” But Allen is himself a former chairman of the National Republican Senatorial Committee, with no shortage of donor juice.

Allen can expect help from his national party organization, which will see the Kaine showdown near the top, if not at the top, of its list of possible pickups. Democrats, looking to hold on to 20 other seats, will be stretched further.

The national context also plays into the donor and party interest: Virginia is a high-profile presidential battleground state, sure to attract the independent campaigns, super PACs and, perhaps, newly unrestricted corporate spending that could inject millions more into the race. Only a few other states promise a similar cocktail of high national interest, high cost and high competition: Florida, where Sen. Bill Nelson (D) is seeking a third term; Ohio, where Sen. Sherrod Brown (D) is seeking a second; and perhaps New York and Arizona.

All of the cash stands to fuel a frenzy of broadcast advertising. And a particular type of advertising.

“Special-interest money tends to be the most attack-oriented. It tends to be the most negative,” said Denton. “The tone itself, it will just invite a lot of punch-counterpunch kind of campaigning. It’s almost like an air war that goes on above the citizens themselves.”

Each candidate has offered plenty of fodder for attack ads. Allen, of course, can expect to see the word “macaca” piped into Northern Virginia homes fairly constantly over the course of months. While Allen can tout his well-regarded tenure as governor in the mid-1990s, some state Republicans also seeking the party’s nomination have already attacked his Senate tenure and most recent role as a political consultant.

As for Kaine? Expect more than a few mentions of rest stops, which he proposed closing late in his tenure to close a budget gap. His opposition to the death penalty will come back up. And here’s a sleeper issue: In his initial appearance as candidate before the state political media Wednesday, Kaine was asked about his late-term recommendation to the Justice Department that inmate Jens Soering, convicted in a 1985 double murder, be sent back to Germany, where he could have been released.

Mc­Don­nell overturned that decision, and Kaine, defending his decision, tried out a novel argument on law-and-order Virginia voters:  “I basically decided, ‘Look, Virginia taxpayers had borne the cost of this German citizen’s incarceration for 20-plus years. I thought it was time for German citizens to bear the cost of his incarceration.”

Expect the merits of that argument, and many others, to be fully explored via several million dollars worth of television advertising.