Updated: Williams vs. Williams?

Updated 6:37 p.m. — There might be more than one Williams in the race for that new Arlington-based congressional district. Former Railroad Commissioner Michael Williams, who had been after Kay Bailey Hutchison's Senate post, switched officially this morning.

And now Roger Williams, a former Texas Secretary of State who's also been running for that Senate seat, is calling around to see if his supporters would back him in that congressional race instead.

Williams and his aides haven't returned calls this afternoon, but several other sources confirmed he is considering a switch.

Both candidates are betting the courts will leave the district, or something like it, in place after appeals of the new political maps drawn this month by the Texas Legislature.

The new district includes parts of Tarrant and Wise counties and all of Parker County; the biggest voting population is in Tarrant. Michael Williams has been working in Austin for more than a dozen years but lives in Arlington and claims it as his residence. Roger Williams has a car dealership and a residence in Weatherford, but votes from a downtown Fort Worth address.

A number of other candidates are also looking, including U.S. Rep. Joe Barton, R-Ennis. He lives in the newly drawn CD-6, and might run there or in the new district. He's the 300-pound gorilla, according to local prognosticators.

"If Joe Barton runs in either of those districts, he'll win," said Bryan Eppstein, a Fort Worth-based political consultant.

Former Arlington Mayor Pro Tem Ron Wright, a former aide to Barton who's now Tarrant County Tax Assessor-Collector, is also considering the race.

 Original story — Michael Williams is officially out of the Senate race and in the race for a new congressional seat based in Arlington.

He said earlier this month he was considering a switch, and now that the Legislature has approved congressional redistricting maps that include the new district, he's filing papers with the Federal Election Commission moving from the Senate contest to the race for Congress.

Williams quit the Texas Railroad Commission after 13 years in April to focus on his federal ambitions. Last Friday, he told Tarrant County Republicans that he was moving to the congressional race and this morning, he posted a letter on his website to the same effect. Though he's had a fulltime job in Austin for more than a decade, he says Arlington is his home. From the letter: "Donna and I have lived in Arlington, Texas for nearly twenty years since returning home from Washington after working for Presidents Reagan and Bush. Our home has been drawn into one of the four new congressional districts, CD-33. The district is anchored by Arlington and includes Parker County, and parts of Wise and Tarrant counties. My parents live here as does Donna’s mother. We love Arlington and are proud to call it home. And I hope to have the opportunity to represent my family and neighbors in Congress."

Williams had been one of a crowd of Republicans hoping to succeed U.S. Sen. Kay Bailey Hutchison, who has decided not to seek reelection next year. That field still includes a number of declared and interested candidates: former Texas Solicitor General Ted Cruz, former Texas Secretary of State Roger Williams, Railroad Commissioner Elizabeth Ames Jones, Lt. Gov. David Dewhurst, former Dallas Mayor Tom Leppert, and state Sen. Dan Patrick.