Chart: How a Campaign Blows Through Millions of Dollars in One Year

— -- Campaigns spend a lot of money these days.

The 2014 House and Senate midterms will cost around $3.67 billion, the Center for Responsive Politics estimates, with over $100 million more in undisclosed "dark money" spent by certain kinds of outside groups.

The campaigns themselves have already reported spending $1.2 billion.

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So where is all of that money going?

Click here for a larger version of the chart.

Senate campaigns aren't required to tell us by Election Day--they submit spending reports to the Federal Election Commission on paper, a seemingly antiquated system that prevents reporters and the public from being able to dig effectively through their latest receipts and expenses. For most campaigns, sortable expense data is only available through June. Weeks or months later, we'll get a fuller picture.

But Sen. Mark Begich, D-Alaska, fulfilling a campaign promise he made in 2008, has been filing his disclosures electronically since October 2013, giving us a window into how Senate campaigns are spending their millions of dollars these days.

Since Oct. 1, 2013, Begich has spent $7.3 million, a middling total for campaigns. Alaska isn't the most expensive state in which a candidate can run, and it's outside the top 10 this election cycle for candidate spending, although, including outside money, it's the sixth most expensive of all 2014 Senate races, according to the Center for Responsive Politics.

The categories are based on those provided by the campaign in its disclosures, and they're lumped together somewhat. Office expenses include things like furniture and phones. Consulting and IT services include things like, well, IT services, but also $142,000 spent through a fundraising-consulting firm, Benchmark Strategies, which was reimbursed for things like travel and food for fundraising purposes, in addition to getting paid.

A campaign spends a lot of miscellaneous money on signs, banners, balloons, etc., but the bulk, as you can see, is spent advertising on TV, radio, and online--a full 58 percent of Begich's budget. Each campaign is different, but the priority on ads was true for President Obama and Mitt Romney, as it's true for Begich's campaign in 2014.

This story has been updated to explain why Begich files his campaign disclosures electronically.