Walsh’s campaign finance report shows a spending surge. Is he gearing up for a reelection fight?

Mayor Martin J. Walsh has significantly more cash than City Councilors Andrea Campbell and Michelle Wu, who are seeking to unseat him.Pat Greenhouse/Globe Staff

Mayor Martin J. Walsh, who hasn’t said if he’s running for reelection next year, increased his campaign spending last month, including doling out more than $50,000 for consultants, new campaign finance data show.

He continues to have significantly more cash in the bank than City Councilors Andrea Campbell and Michelle Wu, who have announced they are running for mayor in 2021.

In September, Walsh’s campaign spent more than $90,000, according to state records. That represents an increase in expenditures compared to recent months; the campaign spent more than $29,000 in August and more than $33,000 in both June and July.

May saw the campaign spend more than $530,000, but that figure included a half-million-dollar donation to the Boston Resiliency Fund, which was set up to help those most in need during the COVID-19 pandemic.

Some political observers say Walsh’s September spending could represent a ramp-up to a reelection bid.

“An uptick in his spending indicates he’s not leaving; it looks more like a preparation,” said Louis DiNatale, a Massachusetts pollster.

Ray La Raja, a political science professor at the Univeristy of Massachusetts Amherst, said politicians who are Walsh’s age “are always running for something.” (Walsh is 53.) La Raja said he wouldn’t be surprised if the Walsh campaign is spending money on focus groups.

“He’s trying to see how tough the race is going to be,” La Raja said.

Candice Nelson, a government professor at American University, said “you can at least assume he’s considering” a reelection bid.

“Why else would he be doing this?” Nelson asked of his campaign activity.

She added: “We’re a year out. If he’s going to run, it’s probably time to start gearing up.”

Last month, the Walsh campaign paid SKDKnickerbocker, a Washington political consultant and strategic communications firm that counts Joe Biden’s campaign among its clients, $36,000. The campaign also paid more than $14,000 to LB Strategies for consulting expenses, according to records.

In a Monday night statement, Walsh said, “I’ve hired SKDK to prepare for what is ahead for 2021 while I’m focused on doing my job as mayor. SKDK has one of the most progressive, most respected, and most experienced campaign teams in the country."

He continued, "But my priority right now is helping our city recover from COVID-19, reopen schools, create new jobs, strengthen our neighborhoods, and keep our city safe. This is a time to be fully engaged in City Hall work, and that’s where I’m focused.”

Walsh’s campaign raised more than $106,000 in September, significantly higher than receipts for the previous three months combined. At the end of September, the campaign had more than $5.5 million in cash, significantly more flush than his two prospective opponents.

Campbell’s campaign had more than $369,000 in cash after spending more than $9,000 and raising $94,000 for the month, according to state records. Campbell announced her candidacy Sept. 24.

“I am so humbled by the enthusiasm and support we have seen in just the first week of my campaign,” Campbell said in a Monday statement. “I am looking forward to building this movement in partnership with residents across this city to transform systems to ensure Boston works for everyone.”

Wu’s campaign had $439,000 on hand at the end of September, according to state records, after spending more than $45,000 for the month and raising $138,000. Wu announced her candidacy Sept. 15, but news of her political intentions had broken a week earlier, when Walsh said the councilor had told him she would be running for mayor.

Walsh has deflected questions about his reelection plans in recent weeks, saying he’s focused on his job. Boston’s voters have not kicked out an incumbent mayor in more than 70 years.