(CNN) On Monday night, President Donald Trump's 2020 re-election campaign announced that it had raised in excess of $18 million over the past three months, a haul that means the incumbent has already raised $106 million for a race that is more than two years away .

That's a stunning -- and totally unprecedented -- amount of money for a sitting president to have collected less than two years into his first term.

Look, I get it. Money has become so plentiful in American politics -- every two years cash floods the system through a variety of super PACs and other newfangled entities aimed at skirting campaign finance law -- that there's a tendency, even among political junkies, to get a little glassy-eyed when it comes to talk of unprecedented amounts of money being harvested earlier and earlier in the election cycle.

But, Trump's haul IS a big deal -- even amid that reality. Here's proof -- in the form of a comparison between Trump's fundraising at this point to his two predecessors in the job:

Trump (fundraising through 9/30/2018)

Raised: $106 million

Cash on hand: $35 million

Barack Obama (fundraising through 12/31/2010)

Raised: $4 million

Cash on hand: $2.3 million

George W. Bush (fundraising through 12/31/2002)

Raised: $3.2 million

Cash on hand: $3.8 million

A little bit of math shows that in three less months of fundraising, Trump has raked in more than 26.5 times what Obama had raised for his re-election race and 32 times what Bush had raised.

The reason for that massive disparity is simple: Neither Bush nor Obama actively sought to raise money for their re-election campaigns during their first two years in office. Bush collected just $265,000 in individual contributions over those first two years while Obama actually refunded more than $179,000 in individual contributions in his first two years.

Why did they make that decision to hold off on fundraising? One practical reason and one symbolic one.

The practical reason is to not directly compete with the party's candidates for House, Senate and governor -- all of whom are on the ballot in midterm elections. Most donors like giving to the president -- it gives them a feeling of prestige and power that cutting a check to a House or even Senate candidate doesn't. So, when given the option, lots of donors will choose to give to the president rather than to downballot races. Sure, there are some contributors who can and will write checks to candidates up and down the ballot. But, it's not all donors -- and the theory is that every dollar a president raises in his first two years in office is money that could have gone to aid his party's fortune in Congress and in governor's mansions around the country.

The symbolic reason past presidents have avoided raising money in their first two years is because they have wanted to send a signal to the country that the campaign is over, they are the president of all the people and they are focused on doing the job to which they were elected not worry about getting reelected immediately. It's the whole there's-a-time-for-campaigning-and-a-time-for-governing thing.

Trump has never played by the political rules. And his decision to file for re-election on the day he was sworn into office is yet more evidence of just how unorthodox he is. He does what he wants -- and usually what he wants is whatever is most advantageous for him. This is one of those instances; whether you like or hate the fact that Trump has already raised more than $100 million for his 2020 race, you can't argue with the fact that it gives him a massive leg up over his eventual Democratic opponent in the chase for campaign cash.

(Sidebar: Can we put an end to the weirdly persistent theory in some political circles that Trump isn't going to run for a second term? This fundraising haul makes clear he's running -- and running hard.)

Trump is a political planet unto himself. Normal rules of gravity don't apply. He does what he wants, when he wants and how he wants. Including raise money. Lots and lots of money.