Where Have 2016 Presidential Donors Given Before?

The candidates running for president are all trying to mobilize different coalitions of voters that have powered past campaigns. A look through their donation records hints at the lineage of each campaign's support.

At least 20 percent of Hillary Clinton's itemized donors to her 2016 campaign also gave to President Obama's campaign in 2008, according to a National Journal analysis matching records from current and past campaign finance reports. Clinton's total from those 4,000 donors alone reaches over $8 million, making up 18 percent of her total fundraising so far for 2016.

Other Democratic candidates are also getting support from the base that powered Obama's 2008 campaign. Of Bernie Sanders's many itemized donors, at least 18.2 percent of them gave to Obama's 2008 campaign. Just under 15 percent of Martin O'Malley's donors matched to Obama's first presidential campaign.

Our analysis provides a conservative estimate of overlapping support. We matched names and zip codes from the Federal Election Commission's donation records across campaigns; typos, name changes, and moving all could have caused shared donors' records not to match. The analysis also omits donors who gave less than $200, since campaigns aren't required to itemize and report those donations.

On the Republican side, the question of who might inherit Mitt Romney's donor network has loomed over the campaign all year. So far, Marco Rubio's campaign has relied most on ex-Romney donors from 2012: Over 35 percent of Rubio's donors gave to the GOP's last nominee and have committed $2.8 million to the senator from Florida so far.

Jeb Bush is also drawing a lot of former Romney donors, while the other two top fundraisers among GOP candidates — insurgents Ben Carson and Ted Cruz — are drawing less from that establishment pool.

Ron Paul recently started sending fundraising emails for his son Rand Paul's presidential campaign, which could bolster the 2016-leading share of donors that Paul the younger is drawing from his dad's old campaigns. At least 14.6 percent of Rand Paul's donors gave money to Ron Paul in 2012.

Mike Huckabee is seeing less than 13 percent of overlap between himself and"¦ himself. Only 12.9 percent of Huckabee's 2008 donors match to his 2016 list, as of the second-quarter FEC filing deadlines in July — though some of that might be because people have moved, changed their names, or otherwise changed info in their filings since eight years ago.

Rick Perry, meanwhile, has relied on donors from his presidential campaign to fill his coffers in 2016, with over one-third of his donors coming from his 2012 list. But part of the reason that Perry has struggled financially so far is that those 2012 Perry donors have actually given far more money to Ted Cruz's campaign so far.

Data.

Behind the scenes post here.

Andrew McGill contributed to this article