President Obama raised about $11.8 million for his re-election campaign during January, according to filings with the Federal Election Commission on Friday, amid signs that overall fund-raising by Mr. Obama and Democratic committees and “super PACs” has fallen behind that of their Republican counterparts.

Mr. Obama remains the presidential race’s top fund-raiser: His total haul for the campaign so far is $151.4 million, slightly ahead of the pace he set in January 2008, during a hotly contested Democratic primary. He also raised $17.3 million in January for the Democratic National Committee.

But Mr. Obama’s January total was less than a third of the $36.8 million he raised during the same month four years ago. (He also spent a third as much this time around as in January 2008.) Over all, Mr. Obama, the leading Democratic super PACs, and the party’s three federal campaign committees raised at least $366.1 million in 2011, compared with the roughly $409 million raised by the Republican presidential candidates, the top Republican super PACs and the Republican Party’s campaign committees.

In a sign of the White House’s concern about Republican fund-raising, Mr. Obama reversed himself this month and instructed administration and campaign officials to aid in fund-raising for Priorities USA Action, a super PAC founded by two former aides. This week, Mr. Obama began a three-day fund-raising swing on the West Coast that was expected to yield more than $8 million, with events in Los Angeles and San Francisco, among other cities. Several other big fund-raisers are scheduled for early next month in New York.