Kent Hehr said Monday he planned to drop out of the Calgary mayor race. (CBC)

A total of 15 candidates have thrown their hats into the ring for Calgary's mayoral race.

But that is down from the 17 who said in the past few months that they intended to run, including Kent Hehr, who decided Monday that he would not run for the top position after all.

Candidates for mayor, alderman and school trustee were required to enter the paperwork for the Oct. 18 municipal election Monday.

There will be contested battles for mayor, all 14 aldermanic seats and the seven positions on the public school board. There are three acclamations for the Catholic school board.

Former alderman Barry Erskine was among those submitting nomination papers and deposit to run for mayor.

"I've been planning this for about three years. I got sidetracked the last little while with my mom getting sick and passing away, but I feel that maybe I'll be the black horse in this probably," Erskine told the CBC.

The current mayor, Dave Bronconnier, has decided not to run again.

Hehr bows out

But Hehr, who was well into the campaign, shocked many Monday when he said he would not file nomination papers, noting that he had neither the money nor the support to mount a successful campaign.

Hehr also scored a disappointing 4.1 per cent in a poll released on the weekend, which weighed heavily in the decision.

"In my heart of hearts, I wanted to keep on going but at the same time, can you continue to expect volunteers and money and all that stuff to keep coming in when, this is a hard business and this is a hard decision?" he told CBC News. "I didn't sleep last night, but this has been wonderful to take part in."

He said that he is not endorsing any other candidate at this time.

The Liberal MLA, who was left a paraplegic at 22 following a shooting, plans to return to his full-time job in provincial politics.

Deadline day

Candidates for mayor must submit a petition signed by 100 voters and a $500 deposit, while people running for the alderman and school trustee positions have slightly lower thresholds.

The city's returning officer, Barb Clifford, said her office had given out almost 200 information packages for prospective candidates since June.

"It's always interesting to see who actually files papers of the many people who pick them up," she told CBC News.

However, Clifford said sometimes candidates fail to follow the correct election guidelines, which prevents them from running.

"We had several people who were short of signatures in 2007 and that was the first time that we had that situation," she said.

Once candidates submit their papers, they have 24 hours to withdraw.

With files from Scott Dippel and Leighton Klassen