Chain Bridge Bank’s single location is next to a wine store and a café on the ground floor of a luxury condo building in suburban McLean, Va., about a half-hour outside downtown Washington. It looks like any small-town bank. Tellers keep bowls of candy at their windows, and staff members talk to customers about no-fee checking accounts. But right now, Chain Bridge, which has about 40 employees, is responsible for more of the hundreds of millions of dollars flooding into the 2016 presidential race than any other bank in the country. According to the most recent Federal Election Commission filings, Chain Bridge is the sole bank serving Jeb Bush’s presidential campaign, which reported raising $11.4 million as of June 30, and his allied super-PAC, Right to Rise, which says it’s raised $103 million so far. Donald Trump’s campaign banks at Chain Bridge, and it’s listed as the primary financial institution for the campaigns of Kentucky Senator Rand Paul and former Texas Governor Rick Perry. It’s also the only bank used by super-PACs supporting neurosurgeon and author Ben Carson, South Carolina Senator Lindsey Graham, former technology executive Carly Fiorina, Louisiana Governor Bobby Jindal, and Wisconsin Governor Scott Walker, all Republicans.