In Wisconsin, Democratic Rep. Tammy Baldwin (above) is facing off against former Gov. Tommy Thompson for the Senate seat.
The NRSC had spent a majority of its IE money in Montana and North Dakota, two offensive opportunities in Republican-leaning states. But they've also spent almost $2 million in Indiana and Maine, which Republicans did not expect they'd need to defend at the beginning of the year.
Maine has been a focal point of the Senate landscape since Sen. Olympia Snowe's (R) surprise retirement announcement in February altered the outlook of that state, kicking off the most unique race of the cycle.
The drama revolves around former Gov. Angus King (I), who is favored to win and is expected to caucus with Democrats. National Democrats have not endorsed their own nominee, state Sen. Cynthia Dill, who has little chance of victory. National Republicans want Dill to take a greater share of the vote to help their nominee, Maine Secretary of State Charlie Summers, catch King. Both national parties have begun spending there, with the DSCC announcing its buy on Friday following an earlier move by the NRSC.
Indiana has roared onto the scene in recent weeks, though the potential for an upset became more of a possibility when Sen. Dick Lugar lost the GOP primary in May to state Treasurer Richard Mourdock, who now faces Rep. Joe Donnelly (D). The DSCC has spent $980,000 there and the NRSC has spent $713,000. Mourdock will be getting even more backing soon from the Club for Growth, which announced on Monday $500,000 in broadcast and cable TV ad buys in both Indiana and Arizona.
The NRSC's first two IEs of the cycle were filed Aug. 31. They were earmarked for ads in support of North Dakota Rep. Rick Berg (R), who is running for his state's open seat against former state Attorney General Heidi Heitkamp (D), and in opposition to Sen. Jon Tester (D), who is being challenged by Rep. Denny Rehberg (R).
North Dakota and Montana are two of the three states, along with Nebraska - which the GOP is currently favored to win - that Republicans must pick up to take the Senate majority. The Senate would be split 50-50 if they're successful in all three, and control would be decided by the outcome of states such as Massachusetts, Nevada, Virginia, Wisconsin and Connecticut.
The DSCC has already dropped $1.2 million in the Nutmeg State, and more is expected to help offset the spending advantage former WWE CEO Linda McMahon (R) has over Rep. Christopher Murphy (D). McMahon has deep pockets and has invested a lot of her own money.
The DSCC has also spent $1.3 million in Nevada, $1.5 million in Wisconsin and close to $1 million in Virginia, where it has plenty more reserved.
The NRSC hasn't spent anything in the Old Dominion yet but has about $5.5 million reserved. American Crossroads and Crossroads GPS, however, have already combined to spend almost $4 million in independent expenditures, which is just a fraction of the overall spending in the state against former Gov. Tim Kaine (D). The one-time Democratic National Committee chairman increased his TV time purchase to $7.5 million and has taken a lead over Allen in recent polls.
Nevada remains a close race between appointed Sen. Dean Heller (R) and Rep. Shelley Berkley (D), who joined first lady Michelle Obama for a rally in Reno on Wednesday.