Two Republicans running in competitive Senate contests are going up with their first TV ads this week, signaling the start of the long slog to the end of the air wars on Election Day.

In New Mexico, Rep. Steve Pearce (R) finally joined Rep. Tom Udall (D) on the airwaves, debuting his first spot this week — a 30-second appeal that focuses on energy. The move comes two months and six ads after Udall hit the airwaves.

Louisiana state Treasurer John Kennedy (R) is also set to begin airing a campaign commercial on Wednesday, following behind Sen. Mary Landrieu (D), who just released her third ad.

Pearce’s campaign declined to reveal the scope of the ad buy but confirmed that it is running statewide on broadcast and cable television. The spot features Pearce talking directly into the camera about the need to increase the use of nuclear energy and wean the country off of its heavy reliance on foreign oil.

Pearce also criticizes Udall in the ad, accusing him of pursuing the wrong energy policy to satisfy the environmental lobby.

“Tom Udall won’t stand up to the far left environmentalists. I will,” Pearce says in the ad. “I’m Steve Pearce and I approve this message because we need to invest in nuclear power and drill for domestic oil.”

Udall is currently on television with an ad in which he discusses his plans for addressing rising gas prices. The spot features Udall at a gas station, as he urges the building of new “clean” oil refineries and blames escalating gas prices in part on “hedge fund speculators.”

Udall, who represents the northern New Mexico 3rd district, is battling Pearce, who holds the southern New Mexico 2nd district, for the right to replace retiring Sen. Pete Domenici (R). Pearce defeated Rep. Heather Wilson in a June GOP primary; Udall faced no opposition for the Democratic nod.

Meanwhile, in Louisiana, a day after Landrieu launched her third ad in the hotly contested race, Kennedy is set to go up with his first television commercial on Wednesday.

Though Kennedy’s campaign declined to discuss how much it is spending to air the new commercial, the ad will appear statewide and will be on broadcast television.

Titled “Brown Bag,” the 30-second commercial is a bio spot that promotes Kennedy’s fiscal responsibility and fight against earmarks during his three terms as treasurer. The ad states that Kennedy is so “cheap” that he brings a brown-bag lunch to work.

“Cheap? Maybe we could use a little of that in Washington,” Kennedy says in the ad.

Kennedy is a former Democrat who switched to the Republican Party last year. Since entering the race, Kennedy has pushed a reform message and his campaign (along with national Republicans who view this race as their only realistic opportunity to defeat a Democratic incumbent) has called Landrieu a symbol of “politics as usual” in Washington, D.C.

Landrieu kicked off the Louisiana Senate air war in mid-July with an ad that pushed her campaign theme that the Senator’s rising seniority on Capitol Hill is an important benefit for Louisiana. Late last month she went up with her second ad, which discusses her efforts to get oil and gas revenue sharing for Louisianans. Her latest ad, released Tuesday, attacks Kennedy for his party switching and calls the Republican a “confused politician.”