Freedom’s Watch, the conservative 501(c)(4) that is aiming to boost Republican Congressional candidates, this week unleashed its first round of television ads in targeted House races.

As of today, the group will be on the air in a half-dozen Congressional districts around the country with ad buys totalling at least $1.3 million.

The buys — a mix of cable and broadcast TV — are all in Republican-held seats, and three of the districts are covered by media markets that are among the most expensive in the country.

Freedom’s Watch does not disclose the size or cost of its advertising buys, so its spending levels are estimated based on the tracking of other media buyers.

The single largest expenditure appears to be in New Jersey’s 7th district, where the group has purchased close to $500,000 in TV time. The substantial cable buy is expected to begin running today in the 7th district race, and a much more scaled-back cable buy, costing roughly $74,000, is also set to begin today in the state’s 3rd district.

The New Jersey contests represent two of the 29 open seats that Republicans are defending in November, and they are also covered by two of the most cost-prohibitive media markets in the country: New York and Philadelphia.

Freedom’s Watch went on the air Tuesday in another expensive market — Chicago — in an effort to help boost the re-election prospects of Rep. Mark Kirk (R-Ill.). The group’s cable buy there is worth about $430,000.

Also on Tuesday, the group went up on network TV in New Mexico’s 1st district, another Republican-held open seat. And, as of today, Freedom’s Watch is expected to be on network airwaves in Nevada’s 3rd district, where Rep. Jon Porter (R) faces a very difficult path to re-election.

Last week the group began airing ads in Alabama’s 2nd district, which is being vacated by retiring Rep. Terry Everett (R).

That TV buy, which cost roughly $150,000, targets Montgomery Mayor Bobby Bright (D) on tax increases. The spot is only running in the Dothan media market, although more than half of the 2nd district is covered by the Montgomery media market, where Bright is well-known.

It encourages viewers to call Bright and tell him to “stop being liberal … with our money.” As a 501(c)(4), Freedom’s Watch cannot directly advocate for or against a candidate’s election and its ads must be based on issues.

Bright, who faces state Rep. Jay Love (R) in November, hit back at the Freedom’s Watch spot in a response ad released this week titled “Vegas and Values.”

“That ad is funded by a Las Vegas casino owner who’s America’s biggest investor in China,” an announcer says in the Democrat’s ad, as a photo of self-made billionaire Sheldon Adelson appears on screen.

Adelson — who in 2006 ranked No. 3 on Forbes magazine’s list of the 400 richest Americans — is believed to be a major funding source for Freedom’s Watch. Because of its tax status, the group does not have to disclose its donors and, therefore, there is no way of knowing who is funding the TV ads.

Freedom’s Watch has spent close to $1 million so far on Senate contests.

The new ads this week represent the group’s first major foray into influencing House contests since its involvement in a pair of special elections this spring. Democrats picked up those seats in Louisiana and Mississippi.

The House GOP has struggled financially over the course of the 2008 cycle, and it has long been expected that Freedom’s Watch would help supplement spending by the National Republican Congressional Committee.

The Democratic Congressional Campaign Committee — which as of this week had spent more than $6.4 million in general election independent expenditures around the country — ended August with $54 million in the bank.

The DCCC has also effectively raised the specter of massive spending potential of Freedom’s Watch, along with Adelson’s largess, to help boost its own fundraising.

The NRCC, meanwhile, showed $14.4 million in cash on hand on Aug. 31 — funds that the committee will have to save for TV advertising in the closing weeks of the campaigns. The NRCC has yet to spend any money on general election TV ads.