WASHINGTON – Pete Buttigieg said Tuesday that he raised more than $19.1 million during the last three months, a decline from the whopping $24.8 million his presidential campaign collected during the second quarter but still a healthy haul.

The fundraising will add to his staying power as the previously little-known mayor of South Bend, Ind., tries to break into the top tier of Democratic contenders in the polls.

Vermont Sen. Bernie Sanders announced he'd collected $25.3 million, an increase from the last quarter.

After raising the most money in the Democratic field in the second quarter, Buttigieg ranked behind only Sanders and Massachusetts Sen. Elizabeth Warren in total fundraising. But he lags behind both senators and behind former Vice President Joe Biden in public polling.

"We will have the resources to go the full distance, and to win, the 2020 nominating contests," campaign manager Mike Schmuhl said in the announcement.

All the candidates haven't announced their fundraising totals for a quarter that typically can be less lucrative than other times of the year. Figures don't have to be publicly disclosed until filed with the Federal Election Commission by Oct. 15, the night of the next Democratic debate.

Buttigieg has ramped up his spending in recent months, opening more than 40 campaign offices in the past quarter and growing the staff to more than 400. He now has more than 220 campaign aides in states that will be casting the first ballots in the nominating contest, according to his campaign.

He’s run two television ads in Iowa in which he’s depicted himself as a pragmatist offering solutions that won’t further divide the country.

"As a veteran, and as a mayor, I’ve seen what we can achieve when we have each other’s backs," he says in one ad. "We need real solutions, not more polarization."

Warren led the field in the latest Des Moines Register/CNN/Mediacom Iowa Poll, with 22% of likely Democratic caucusgoers saying she is their first choice for president.

Biden was second with 20% and Sanders at third with 11% in the poll conducted Sept. 14-18.

Buttigieg followed the three leaders as the favorite of 9% of poll respondents.

That's below the 14% support he drew in Iowa in June. But just one in five likely Democratic caucusgoers told pollsters in September that their minds are made up, illustrating the fluidity in the race.

Buttigieg's campaign emphasized how much his national support has grown since entering the race at the beginning of the year. The number of donors has increased from fewer than 200,000 in the first quarter to more than 580,000 today, according to the campaign. The average donation is about $40.

Top fundraising moments for the past few months include the July and September debates, a lottery for contributors to win "pizza with Pete," and a final push at the end of the quarter that included the first fundraising solicitation written by his mother and an appeal sent out an hour before the deadline.

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