The Senate Leadership Fund plans to spend big money defending Republicans in a quartet of battleground seats this fall, the super PAC said Tuesday, a strong indication of which states the group expects — and doesn’t expect — to be competitive in November.  

Headlining the fund’s list of TV ad reservations is a $15.8 million buy in New Hampshire, where Republican Sen. Kelly Ayotte and Democratic Gov. Maggie Hassan are expected to face off in one of this election cycle’s marquee races.   

The nearly $16 million spent in tiny New Hampshire is a gargantuan sum, even in the expensive Boston media market. It’s partly a reflection of the fact that the well-financed political network of Charles and David Koch, which has spent heavily defending a handful of Republican incumbent senators so far this election, has said it will not help Ayotte win re-election.   

In the entirety of his 2014 race in the Granite State, Republican nominee Scott Brown raised less than $10 million .   

The group said it also plans to spend $6.2 million in Pennsylvania, $8.1 million in Ohio, and $6 million in Nevada. Pennsylvania and Ohio are represented by Republican Sens. Patrick J. Toomey and Rob Portman, respectively, and Democrats have targeted both as prime pickup opportunities in 2016.   

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Nevada is potentially the GOP’s only realistic chance to win a Democratic-held seat in 2016. Republican Rep. Joe Heck is taking on former state Attorney General Catherine Cortez Masto for Senate Minority Leader Harry Reid’s seat. Reid is retiring.  

Political strategists caution that ad reservations can and often do change. But where groups like the Senate Leadership Fund say they are going to run TV ads is an important signal for other super PACs, candidates, donors, and party committees, which can adjust their own spending accordingly.   

The leadership fund is part of a network of establishment-friendly outside groups connected to Karl Rove and Senate Majority Leader Mitch McConnell. The best-known of these groups, American Crossroads, focuses on the presidential race.   

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The ad buys also include $2.5 million slated for Missouri, where Democrats believe they have a chance to upset Republican Sen. Roy Blunt with the candidacy of Secretary of State Jason Kander. Republicans, who have already spent money defending Blunt, contend that they are only trying to shore up Blunt’s position with early spending (the leadership fund’s reservation doesn’t include time in October) to make sure the race isn’t a problem later.  

But Democrats will point to the spending as evidence that Kander, who may be the favorite candidate of party strategists in Washington, has scared the GOP.  

Democrats will also delight in the omission of two Republican incumbents: Sens. Mark S. Kirk of Illinois and Ron Johnson of Wisconsin.   

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Many Republican strategists consider Kirk, running in deep blue Illinois, a lost cause. Opinions are more divided about Johnson, and groups like the Koch-backed Freedom Partners Action Fund and the Chamber of Commerce have spent on his behalf this year.    

The Senate Leadership Fund did not list an ad buy for Florida but added that it plans to announce spending there in the coming weeks now that Sen. Marco Rubio has decided to run for re-election.   

Contact Roarty at alexroarty@cqrollcall.com and follow him on Twitter @Alex_Roarty
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