Every election cycle the political world watches two sets of races: one between candidates for office, and another equally competitive battle between political consultants, ad-makers and digital marketing gurus for slices of the lucrative campaign expenditure pie.

This year, several firms affiliated with past presidential campaigns are among the early winners, according to data analyzed by the Center for Responsive Politics.

DC-based Waterfront Strategies, a branch of political consulting behemoth GMMB, has raked in the most business during the 2014 cycle, with almost $42 million in media buys on behalf of liberal PACs. GMMB was a huge winner in 2012, collecting more the $300 million in gross receipts from Obama campaign spending alone.

Automatic Data Processing, a Virginia-based payroll and human resources management firm, sits in second place so far this year with just over $22 million in revenue from political clients.

While coverage of political expenditures tends of focus on flashy ad producers and digital whiz kids, the top 10 list reflects the reality that campaigns and PACs from both parties rely on plenty of mundane, but indispensable services. Southwest Publishing & Mailing produces direct mail materials, Strategic Fundraising runs telefundraising call centers, and FLS Connect -- a major consultant to the 2012 Romney presidential campaign -- specializes in electoral data and phone banking. Direct mail and phone banks may not grab headlines, but they have managed to pull in more than $13 million for those three firms during this cycle.

In the confined business of campaign consulting and services, the list of top political expenditure recipients during midterm years sends an important signal about who’s in and who may be out ahead of even more lucrative presidential elections. The 2012 Democratic heavyweights Bully Pulpit Interactive and Blue State Digital, as well as key Romney-allied digital firm Targeted Victory, for example, are all so far absent from the top of the 2014 list.

While consultants and digital strategists may stay active in the business of political campaigns for decades, a connection or early relationship with an ascendant candidate can often mean the difference between competing for smaller accounts and making millions off a national campaign. Rising Tide Interactive, a digital firm favored by the pro-Clinton super PAC Ready for Hillary, has already emerged as 2014’s most-used online ad provider, according to CRP’s data.

Two beneficiaries of campaign spending, at least, seem likely to remain in the game no matter who’s running for office: The US Postal Service has already made more than $17.5 million this cycle, and the IRS has collected over $13 million in payroll taxes. No matter who's on top, Uncle Sam always gets a piece of the action.