Sekula Gibbs, a former Houston City Council member, temporarily held the office after DeLay resigned his congressional seat in 2006 following his indictment in a Texas campaign finance case. Olson is a former aide to U.S. Sens. Phil Gramm and John Cornyn.
The congressional contest could be affected by turnout in the race for district attorney of Harris County, which includes Houston. Kelly Siegler, a flamboyant prosecutor, battled Pat Lykos, a former police officer and judge, for the Republican nomination.
Chuck Rosenthal resigned as district attorney amid a contempt of court charge and a scandal involving racist, pornographic and political e-mails found on his county computer. Some were sent by Siegler's husband, physician Sam Siegler. Kelly Siegler attempted to distance herself from the e-mails but has been taking heat for her unorthodox, rule-bending courtroom style.
Lykos says the office needs a leader who's not connected to the scandals.
The GOP winner will face Democrat C.O. Bradford, a former Houston police chief whom Rosenthal once charged with perjury. Bradford was accused of lying under oath about the chastising of a subordinate, but a judge summarily acquitted him after prosecutors laid out their case.
In Austin, two Democratic assistants to Travis County District Attorney Ronnie Earle -- Rosemary Lehmberg and Mindy Montford -- competed for the chance to succeed him. Earle, whose office investigates alleged corruption in state government, brought the charges against DeLay, who maintains his innocence and claims the case against him is politically motivated.
In California, former legislator Jackie Speier had big advantages in fundraising and name-recognition over her rivals for the San Francisco-area congressional seat held by Rep. Tom Lantos before his death in February.
Leo Ryan held the seat in 1978, when he was killed while on a fact-finding trip looking into the Jim Jones cult in Guyana. Speier, also on the trip as an aide to Ryan, was seriously wounded before Jones and 912 of his followers died in a mass murder-suicide.
Speier, a 57-year-old Democrat, has since represented much of the area within the 12th Congressional District as a San Mateo County supervisor, assemblywoman and state senator.
Democrat Michelle McMurry, Republicans Greg Conlon and Mike Moloney and Green Party candidate Barry Hermanson also are in the running to finish Lantos' term. If no candidate gets more than 50 percent of the vote there will be a June 3 runoff.
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