Story highlights Trump has repeatedly said he would contribute more than $100 million to his campaign by the end

To back up that statement, he would now have to contribute more than $40 million

(CNN) Donald Trump cut his routine $2 million monthly check to his campaign last September after repeatedly suggesting that he would increase his donations during the campaign's stretch run.

Trump's campaign, along with Republican joint fundraising committees, said it raised $100 million last month, more than it has in any previous month though well short of the $154 million Hillary Clinton's operation took in.

But Trump -- who largely closed a polling gap with Clinton during much of September -- did not give more to his campaign than he had in previous months despite being pressured to invest more of his fortune.

His campaign did not specify how much of the money was raised by his campaign versus the committees, which must split proceeds with the Republican National Committee and more than 20 state parties.

Meanwhile, a new fundraising report filed Saturday night found few Republican heavyweight donors cut major checks to Trump's campaign during the summer months.

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