Voters are poised to learn Friday when special primary and general elections will be held to replace former state Sen. Michael Rubio, who resigned last month citing a need to spend more time with his family.

Gov. Jerry Brown had 14 days from the time Rubio announced his resignation -- which was Feb. 22 -- to set the date of the special elections, giving him until Friday, when he's expected to make an announcement, said spokesman Evan Westrup.

The special general election must happen on a Tuesday between 126 and 140 days after that announcement, and a special primary has to be held on a Tuesday nine weeks before the special general election. Those rules would put the special primary election sometime in May and the special general election sometime in July.

That means it wouldn't coincide with the June 4 special election that's been called to replace Rudy Salas on the Bakersfield City Council.

Already, one big-name candidate has dropped out of the running for the 16th Senate District post Rubio just left. Former Assemblywoman Nicole Parra told The Californian Thursday she won't run.

"I am so humbled and honored that so many people in the Central Valley would like me to run for the open Senate seat vacated recently," Parra said in a statement. "Democrats, Republicans and Independents reached out to me and my family and I am truly honored.

"After many discussions with my family and friends, I have decided not to run for the open Senate seat."

Parra said she's accepted a job as senior vice president for public affairs for Global Regenesis, a new company "centered on environmental stewardship and alternative energy based on bio waste fuel streams."

It will be located in the San Joaquin Valley and is the United States arm of a London-based operation, she said. Parra said she will be working in Sacramento, Washington, D.C., and London.

Parra represented the 30th Assembly District as a Democrat from 2002 to 2008. She has since been unaffiliated with any political party.

The names of several other politicos have been bandied about as potential candidates to replace Rubio.

On the Democratic side they include Leticia Perez, Kern County supervisor of just three months; Salas, state Assemblyman also of only three months; Fran Florez, Shafter councilwoman and onetime Assembly candidate; and Fresno County Supervisor Henry Perea.

A spokeswoman for Perez said the 5th District supervisor didn't want to comment Thursday on the matter but stood by earlier statements.

Last week, Perez said she's received an "outpouring of support" from people encouraging her to run and that she'd announce a decision after Brown names dates for the special elections.

Florez didn't return a call seeking comment Thursday.

Salas tweeted on Saturday: "Lots of discussion about future of #SD16 seat. Flattered with the overwhelming calls. Looking forward to doing what's best for our community."

He couldn't be reached Thursday.

Also mulling a run is Democrat Richard Valle, a Kings County supervisor.

Valle said his constituents spurred him to consider a bid for the seat. Valle is two months into his second four-year term as a Kings County supervisor. He's also a former Parra field representative.

"I've just spent the last couple of days gathering wood to see if I could build a fire," Valle said. "I'm strongly considering" a run. He added that he'll make an announcement about a decision "in the next couple days."

There's a void in leadership in the state legislature for Central Valley representation, he said.

"I'm not looking to bail on my constituents," Valle said. "I'm offering this public service because there is a void right now in Sacramento."

Alfred Benavides, a former school board trustee and frequent political candidate from Kings County, said last week he will run.

On the Republican side, Salas' former rival for the state Assembly seat, Pedro Rios, said Thursday he was taking a wait-and-see approach.

Rios said he is awaiting the outcome of a survey of voters by the state GOP to gauge which Republican candidates, including him, would be strong contenders.

"If there is another solid Republican candidate ... I would support that candidate," Rios said. "However, if it came down to me being that candidate, I would hope that they would also support me. We want to win that seat. It's important to us."

If the state party asks him to run, Rios said, "I'm going to be there, you bet."

"(In) part of the district, I have that name ID already because the election that took place just three months ago," Rios said of the hard-fought and expensive 32nd District race he lost to Salas.

But Rios said that if Andy Vidak, another Republican whose name has been floated as a possible contender, runs, he would step aside. Vidak, a Hanford farmer, unsuccessfully challenged Rep. Jim Costa, D-Fresno, for Congress in 2010.

Other Republican names being floated include Assembly Minority Leader Connie Conway, who represents the Kern River Valley, and Bakersfield City Councilman Russell Johnson.

"She is flattered by all of the talk about her being considered for that race," said Conway spokeswoman Sabrina Lockhart. "She understands why folks are talking about it since she has represented part of that district both in the Assembly and in her previous supervisor seat. It's always good to have options."

Johnson did not return a call Thursday.

Parra, when asked if there's anyone she would like to see run, said "there are a lot of good candidates out there, I just wish a few of them had completed a full term in office before they consider running."

She said she considered Perez a friend and "wishes her the best regarding her decision." Parra said Valle did a great job when he worked for her.

And, Parra said, Vidak would be a good candidate, too.

Republican political consultant Stan Harper said that on the GOP side, Vidak would be a top contender given his name ID. He said he doesn't think Conway will run.

Harper said that of the Democrats, Perez would have the best shot given her built-in support from the Rubio camp (she used to work for Rubio) and her proven field operation from last year's supervisor's race.

"She's got the ground game covered," Harper said.

Perez would take flak, though, for seeking another post after just a few months on the Kern County Board of Supervisors, Harper said.

He guessed Salas won't run because he'd face even harsher criticism if taxpayers have to spend considerable money on not just one but two special elections to replace him in an office.

"Republican candidates would eat him alive on that one," Harper said.