They have been coy so far, but come Monday the men and woman who want to be Philadelphia's next mayor need to show their hands.

That is the deadline to file finance reports for campaign funds raised in 2014. The figures revealed in those reports will go a long way toward determining the true pecking order among candidates.

They should also offer a hint as to how much more life will be injected into a campaign that has morphed in the last week from a rather sleepy affair into a potential barn burner.

At the moment, there is every indication that money is tight, and few if any of the current crop of declared candidates in the May 19 Democratic primary have raised anything close to the figures reported eight years ago when there was a similarly wide-open race without an incumbent.

Michael Nutter raised and spent $6.8 million over two years to win that 2007 contest. Political professionals say a credible bid to succeed him could cost as little as half that.

Talk to those professionals and they offer a variety of reasons to explain why they believe fund-raising is down from 2007: a regional economy that is still relatively weak, donor fatigue from the just-concluded Pennsylvania governor's race, City Council President Darrell L. Clarke's dithering over whether he would run for mayor, and - ironically - the city's strict fund-raising rules, which were meant to make campaign financing more democratic but instead may have simply dampened it.

What is not in dispute is that all evidence at the moment points to a very weak fund-raising season.

For instance, the campaign has already lost one candidate - Terry Gillen - who specifically pointed to the difficulty of raising money as a reason she pulled out.

"The money was a big factor," Gillen, the former head of the city's Redevelopment Authority, said Jan. 2 when she left the race. She said she had raised more than $225,000 from more than 500 donors - and it wasn't enough.

"It was a question of whether we would have the money to run the kind of campaign we wanted to run," Gillen said.

There are indications, too, that Ken Trujillo, the former city solicitor who withdrew from the race last week citing family issues, was not necessarily setting fund-raising records. One source placed donations to Trujillo's campaign at about $400,000 - not insignificant, but nothing like the figures reported by candidates eight years ago.

Funding was so prolific in the 2007 race that three Democratic candidates - Nutter, State Rep. Dwight Evans, and U.S. Rep. Bob Brady - did not wait for the filing deadline to brag that they had already raised more than $1 million.

In contrast, none of this year's candidates were willing to release their totals early, a not-too-subtle clue the numbers might not be spectacular.

Another hint that money is tight is the lack of television advertising so far in a race where most of the candidates are still not widely known to voters.

At the moment, the announced candidates are former District Attorney Lynne M. Abraham, former Common Pleas Court Judge Nelson A. Diaz, and State Sen. Anthony H. Williams. Still to formally enter the race are former State Sen. T. Milton Street and Doug Oliver, former spokesman for Nutter. Sources speaking on condition of anonymity said Friday that City Councilman James Kenney has also decided to run.

"If anybody had the funds, they would be up on television already," said Larry Ceisler, a local media consultant.

Ceisler offered several reasons for believing this will be a weak fund-raising season. The first was Clarke's belated decision not to run for mayor himself.

"Darrell Clarke froze the field," Ceisler said. "There were a lot of people who, even if they were not planning to support Darrell, had to wait to see what he was going to do."

Another issue, Ceisler said, is the candidates themselves, few of whom have had to run in previous contests under the city's strict fund-raising rules, which limit giving to $2,900 for individuals and $11,500 from organizations.

Fund-raising is an acquired skill, Ceisler said, and it is not surprising that the untested might find it difficult.

The campaign limits themselves have been the target of complaints by a number of candidates and observers who contend that the rules, while the product of good intentions, have had the effect of making it harder to run for office without the backing of third-party interest groups that do not fall under the same regulations.

Oliver touched on the issue in a posting on his "DO2015" website.

"If you believe that it takes $4m to run a credible mayoral campaign, then you must also believe that you can find approximately 1,400 people willing to give you the maximum contribution of $2,900 in one of the lowest income cities in the country," he wrote. "Even if you allow for PAC contributions, it's tough to envision where the 'necessary' money comes from. This discourages potential candidates."

City Controller Alan Butkovitz, who has also flirted with a mayoral run, holds similar views.

"The Philadelphia campaign finance rules are among the most restrictive in the country," he said. "And they make it difficult to raise money from people interested in city elections."

Butkovitz was particularly troubled by rules that put a $11,500 limit on donations from law firms or partnerships that might do business with City Hall. As a result of the rules - designed to curb the "pay to play" tradition of city work going to big mayoral donors - contributions have all but dried up for candidates, he said.

While that might be seen as a good thing in reform quarters, it leaves candidates more dependent on third-party entities and political action committees that have fewer requirements when it comes to fund-raising and accountability.

"The irony is that while people live by these rules, they are struggling to find ways to get big money into the race," Butkovitz said. "And that has to do with independent expenditures, super PACs, and all sorts of loopholes which act contrary to the original intent of the law - which was to get rid of all the big money."