LetsFlipCongress.org is the product of concerned citizens working in their free time.

Concept and implementation by Ed Baskerville, who by day does quantitative modeling for infectious disease research. Promotional work and graphics by Mattie Kaiser, Lizzy Baskerville, and Heather D’Angelo. Valuable feedback from many friends, family, and strangers.

Copyright ©2018 Ed Baskerville.

This sounds really great. But how do I trust LetsFlipCongress.org? How do I know that my money will go where I intend it to?

You don't have to trust us, since you don't enter any payment information whatsoever into LetsFlipCongress.org. After we calculate how much to give to each candidate, we send you over to ActBlue, the payment processor used by all Democrats. You give your information to ActBlue on their website, not on this one.

So, how does it work again?

We use FiveThirtyEight's win probabilities—specifically, from their Deluxe model—to calculate how much different races get out of your total contribution. In short: more to closer races, less to distant races.

ActBlue has a feature that allows citizens to set up pages that donate to multiple candidates at once. That’s what we have done. Our page has the 22 closest Senate races and more than 100 of the closest House races. After calculating how much to give to each candidate, we fill in the amounts for you. Effectively, you are using ActBlue to make donations to individual candidates’ campaigns.

So this is exactly as if I donated directly to the candidates one at a time?

Yes.

Do I have to donate exactly the way you tell me to?

No. You can add/remove candidates using checkboxes on the Review Donations page. For example, you could uncheck Joe Manchin, if you were so inclined, and the money allocated to him would be redistributed to the other candidates.

How do you decide which candidates are included?

We currently include all House candidates that have between a 1% and a 99% chance of winning. We include all Senate candidates who would get at least as much as a 1%-chance House candidate, assuming you donated the same amount to each chamber.

You don't take any money. How much does ActBlue take?

According to ActBlue's website, they charge candidates a processing fee to cover the cost of credit card fees, etc. Again, this is the same as if you donated online directly to the candidate. Beyond that, ActBlue asks for a tip after you give, but that’s totally optional.

How do I trust the ActBlue website?

If you know anyone involved in Democratic or progressive politics, you can verify with them that ActBlue is a trustworthy organization. If you have some tech-savvy friends, they can easily verify that the website we use really is ActBlue.

When I donate to an individual candidate, I get on their email list. Does that mean I’m going to get on every candidate’s list?

Yes. The easiest way to get around this is to set up a separate email address for junk mail. Or you can click unsubscribe in the first message you get from each candidate. You can also select fewer candidates on the Donation Review page.

Do you and ActBlue get my contact info?

Yes. We’re not sure why ActBlue gives us access to your contact info, but they do. We promise not to use your contact info for anything except a follow-up survey after the election, so we can try to get feedback for the next time around.

How exactly do you calculate the amounts?

The model is actually very simple. We give money to candidates proportional to how much we think your money will *increase* their chance of winning. If you’re probably far behind, more money won’t help: your chance of winning is zero. The same goes for being far ahead. But if you’re close to 50%, more money will help a lot.

Mathematically, as a candidate’s vote share goes up, the probability of winning a race goes up according to a “sigmoid curve”. In the absence of a more sophisticated model, we assume that a dollar increases the vote share by the same amount in every race, so we can treat an increase in funds as an increase in vote share. We assign amounts proportional to the *slope* of this sigmoid curve.

Really mathematically: we assume the sigmoid curve is the cumulative distribution function of a t-distribution with 7.14 degrees of freedom. We use that particular curve because it fits the relationship between win probability and vote share in FiveThirtyEight’s forecasts, which we use as the basis for our calculation.

There should be a picture here, but we haven’t made one yet.

What happens if the calculated amount is very small (less than $1)?

If you donate less than $1000 or so, the calculated amounts for many of those candidates will be less than a dollar, which is ActBlue’s minimum donation. For those candidates, we randomly round up or down to $0 or $1. For example, if the calculated amount is $0.25, there’s a 25% chance they’ll get $1, and a 75% chance they’ll get $0.