Ontario Mayor Paul Leon is one of six candidates competing in what he calls a "sprint" to succeed Gloria Negrete-McLeod in Senate District 32.
The primary contest is scheduled to take place March 12.
The candidate list became official last Friday, and Leon held a campaign event Tuesday outside the offices of Landmark Medical Management in Ontario.
What made the event a little more interesting than the average political gathering is the fact that Landmark's president is Kareem Ahmed, a major donor to Democratic groups and candidates.
The small irony did not go unnoticed during a moment of levity inside Ahmed's office, where the executive has pictures of himself with President Barack Obama, House Minority Leader Nancy Pelosi and former President Bill Clinton.
"The only Republican that I am big-time supporting is Paul," Ahmed said to a small group gathered inside his office.
"Kareem's a little close to the president," Leon said before a short pause.
"Which is OK," he continued.
Ahmed said he is supporting Leon because of the help he received from Ontario's mayor in dealing with City Hall while setting up his offices in Ontario.
Leon's campaign priorities include supporting business, directing Proposition 30 revenues to schools and reducing taxes.
"My No. 1 goal will be to bring jobs back to California," he said.
Leon also said that, if elected, he would introduce legislation to help Ontario take over L.A./Ontario International Airport from Los Angeles.
"It's my intention to get Sacramento involved in the airport issue," Leon said. "There's a multitude of different ways that I have in mind, and I'm not ready to tip my hand. I'll do it when I'm there."
In 2012 alone, Ahmed donated $1.2 million to Democratic groups including Priorities USA, a Super PAC that supported President Barack Obama's re-election campaign.
Ahmed also gave more than $40,000 to candidates for federal office, including McLeod, whose election to Congress cleared the way for Leon and his five competitors to seek the seat.
Whoever wins the special election will serve out the remainder of McLeod's Senate term, which expires in 2014.
The field of candidates includes two Republicans: Leon and fellow Republican Kenny Coble, the general manager of a construction firm and a Pomona planning commissioner.
Democrats in the race are Ontario Councilman Paul Vincent Avila, Rialto Unified school board member Joanne Gilbert, Assemblywoman Norma Torres and San Bernardino County Treasurer/Tax Collector Larry Walker.
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