Richardson had been working with Liljenquist for months, helping him build up an organization and message for a potential Senate bid.
She joined the Legislature a year ago after Rep. Craig Frank was ousted from the body when it was discovered he didn't live within the boundaries of House District 57.
Richardson, who has 24 children 20 of them adopted writes the "Holly on the Hill" blog, which helped to build her profile in the conservative community. Before becoming a lawmaker, Richardson, who is also a registered midwife, was active in lobbying lawmakers to adopt laws more friendly to home births.
All told, Richardson is the tenth lawmaker to resign or leave office since the 2010 elections. Two left to take jobs in Gov. Gary Herbert's administration; two resigned for personal reasons; Frank left amid the boundary dispute; Sen. Dennis Stowell, R-Parowan, passed away; and four, including Richardson, resigned to campaign for higher office, although the other three are themselves candidates.
Liljenquist, R-Bountiful, stepped down last month to run against Hatch. Former House Speaker Dave Clark, R-Santa Clara, also resigned in December to run for the 2nd Congressional District. Rep. Carl Wimmer, R-Herriman, submitted his resignation Thursday afternoon so he could run for the 4th Congressional District seat.
Utah law prohibits legislators from raising money during the 45-day session, which begins Jan. 23. That and the time demands of the session make running a campaign difficult, although several legislators are seeking other offices while serving.
Frank said Friday that he plans to compete for the seat he was bounced from less than a year ago. He said he has moved his home to Pleasant Grove and lives in the current district boundaries and those that will be in effect for the next election.
Michelle Smith, a mother of seven, also said she was running for the District 57 seat and vowed to donate her legislative salary to schools. She said she had been endorsed by Parents For Choice In Education, a group targeting education reform, as well as the pro-business Utah Taxpayer Association.
Brian Halladay, legislative District 57 chairman, said he had heard that Richardson would be stepping down, but didn't know it would be so soon.
"Obviously [her time] was short," he said. "I don't know whether she knew she was going to be taking this action when she jumped into the race. I would hope she didn't. I think she's doing what she feels like she needs to do and I'm sure our district can elect someone to that position in the short time frame who will be good for the district."
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