After raising $100 million in partnership with Republican Party organizations in September, Mr. Trump and committees linked to his campaign began October with $75 million in cash on hand. Mrs. Clinton raised $154 million in September and began October with roughly $150 million in the bank, her campaign said, twice as much as Mr. Trump.
That gives Mrs. Clinton a huge war chest for last-minute advertising and organizing at a time when she has regained her lead in public opinion polls and Mr. Trump has become mired in accusations that he groped women.
Even so, the monthly figure was a record for Mr. Trump and provided evidence of his powerful appeal among grass-roots donors: The campaign now estimates that 2.6 million people have given to his campaign. But it was only a small improvement over his fund-raising in July and August, suggesting he might have peaked.
Moreover, Mr. Trump has so far not followed through on promises to spend $100 million of his own fortune on the campaign. In September, he contributed $2 million, his usual amount since he became the Republican nominee, leaving him roughly $44 million short of his goal.