It’s a problem for the Republican party that their party is comprised mostly of senior citizens. Given that, it seems like a rather simple conclusion that, over time, it will becoming increasingly difficult for Republicans to produce numbers at the polls.

In a recent post at Politico, Daniel McGraw tried to figure out exactly how widespread the problem is for the Grand Old Party:

By combining presidential election exit polls with mortality rates per age group from the U.S. Census Bureau, I calculated that, of the 61 million who voted for Mitt Romney in 2012, about 2.75 million will be dead by the 2016 election. President Barack Obama’s voters, of course, will have died too—about 2.3 million of the 66 million who voted for the president won’t make it to 2016 either. That leaves a big gap in between, a difference of roughly 453,000 in favor of the Democrats.

Here is the methodology, using one age group as an example: According to exit polls, 5,488,091 voters aged 60 to 64 years old supported Romney in 2012. The mortality rate for that age group is 1,047.3 deaths per 100,000, which means that 57,475 of those voters died by the end of 2013. Multiply that number by four, and you get 229,900 Romney voters aged 60-to-64 who will be deceased by Election Day 2016. Doing the same calculation across the range of demographic slices pulled from exit polls and census numbers allows one to calculate the total voter deaths. It’s a rough calculation, to be sure, and there are perhaps ways to move the numbers a few thousand this way or that, but by and large, this methodology at least establishes the rough scale of the problem for the Republicans—a problem measured in the mid-hundreds of thousands of lost voters by November 2016. To the best of my knowledge, no one has calculated or published better voter death data before.

That means that, if nothing else changes and time and nature simply take their course, the Democrats will gain approximately 453,000 votes. Admittedly, there are complicating factors that could produce variations within that figure. It is however a strong indicator that the GOP has a problem. It doesn’t connect with younger voters and it is quickly dying out.