Members of Congress usually only have a broad concept of how something will affect their constituents -- if it affects their districts at all. But the Republican health care bill is a notable exception, given the Congressional Budget Office's estimate that 24 million fewer people would be insured come 2026.

And one key data point drives home just how tough today's vote will be, district by district, for House Republicans.

In this case, we can take the CBO score and get a pretty good idea of how that prediction would pan out for each individual member. Which is exactly what the left-leaning Center for American Progress has done.

That 24 million spread out evenly over 435 districts would translate to about 55,000 people losing or dropping coverage in each district. But CAP went the extra mile and made estimates for each district based on their demographics and policy decisions made in each state. It's from a left-leaning think tank that opposes the bill, yes, but it's based on the nonpartisan CBO's overall estimate, and the grand total is the same.

CAP estimates, for example, that about 88,000 fewer people would be covered come 2026 in GOP Rep. David Valadao's California district  -- a much-bigger share than the national average. For Rep. Dan Donovan (R-N.Y.), the number is about 85,000. For Rep. Jeff Denham (R-Calif.) it's about 84,000.

Just how significant are those numbers? Well, in all three cases, these members were elected or reelected in the last midterm election in 2014 with fewer votes than that. Valadao got about 46,000 votes, Donovan got 59,000 and Denham was just north of 70,000. All three of them won by between 12,000 and 16,000 votes.

So it doesn't take a huge backlash; if even a significant portion of the people who lose or drop insurance in these districts are upset about it, this is clearly a vote that can give these Republicans problems. It's something that could hurt them even if it's just on the margins -- and even if the CBO's 24 million estimate overshoots the target.

That 24 million estimate, of course, is where things would be in 2026 -- not by the 2018 midterm election. The CBO estimated that 14 million would lose or drop their coverage by 2018. But in each case, that's still tens of thousands of potential voters for Valadao, Donovan and Denham, according to the CAP estimate. (Both Valadao and Denham have been targeted by ads urging them to support the bill -- perhaps a nod to the tough math in their districts -- but haven't said how they'll vote. Donovan opposes the bill for the burden he says a New York-focused provision would put on his Brooklyn and Staten Island district.)

Member Uninsured increase by 2026 (per CBO) Total votes in 2014
Rep. David Valadao (R-Calif.) 87,800 45,907
Rep. Daniel Donovan (R-N.Y.) 85,200 58,886
Rep. Jeff Denham (R-Calif.) 83,700 70,582
Rep. Lee Zeldin (R-N.Y.) 89,400 94,035
Rep. Elise Stefanik (R-N.Y.) 85,700 96,226
Rep. Will Hurd (R-Tex.) 42,400 57,459
Rep. John Faso (R-N.Y.) 90,800 131,596

It's also tens of thousands of people projected to lose insurance for vulnerable GOP members like New York's Lee Zeldin (89,000 uninsured by 2026), New York's Elise Stefanik (86,000), Texas's Will Hurd (42,000) and New York's John Faso (91,000). In each case, even if half that number become uninsured by 2018, that's still 40 percent-plus of their entire vote total in the last midterm.

As The Post's Fact Checker has emphasized, just because fewer people will be insured doesn't mean all of them will have lost their coverage; some may prefer it that way. But the CBO's projection of much higher premiums for older, poorer people and the rollback of the Medicaid expansion, in particular, threaten to take insurance away from people who are currently able to access it under Obamacare.

That's a recipe for people being upset, and it's not even that difficult to game out how it could come back to bite individual Republican members at the ballot box.

House Republicans on March 6 released legislation that would substantially alter the Affordable Care Act. Here’s what you need to know about the plan. (Bastien Inzaurralde, Sarah Parnass, Jenny Starrs/The Washington Post)