Republican Kay Bailey Hutchison insists she will quit her Senate seat this year, whether she wins or loses her challenge to incumbent Gov. Rick Perry in today’s Texas primary. She has remained adamant about her departure even though the primary, once billed as a battle of political titans, has shifted strongly in Perry’s favor.

But the only resignation so far is the feeling among would-be successor candidates who have had to wait while Hutchison repeatedly — and as recently as last Friday — moved her departure date further into the future.

“It doesn’t affect what we’re doing,” said Roger Williams, a businessman and former Texas secretary of state. Williams has been positioning himself against other Republican hopefuls in what is described as a shadow campaign for the special election that would follow a resignation by Hutchison, whose Senate seat is next up for election in 2012.

“If we focus on the date when she resigns, it gets us off the mark,” Williams said.

Senate prospect Michael Williams, unrelated to Roger Williams and a state railroad commissioner, expressed a similarly sanguine view. Michael Williams, a conservative who has the endorsement of Sen. Jim DeMint (R-S.C.), said he “is fully prepared to serve if called upon and committed to run when the time comes.”

Hutchison initially said she would resign from the Senate by mid-2009 to focus on her challenge to Perry, who moved up from lieutenant governor in 2000 after predecessor George W. Bush was elected president. Perry has since won election in 2002 and 2006 and already is the longest-serving governor in Texas history.

But Hutchison then deferred her resignation until last November, and then again until after today’s primary. The latest iteration, delivered during a radio interview in Texas on Friday, is that she will leave “sometime this year before the November elections.”

As she did last fall, Hutchison tied her new timeline to the fiercely debated Democratic-led effort to overhaul the nation’s health care system, saying, “I’m going to stay and fight health care. I promised that, so that’s my first commitment, and I will do that.”

The “will she stay or will she go” question surrounding Hutchison has placed John Cornyn, the other Republican Senator from Texas, on the long horns of a dilemma.

He is a longtime ally of Hutchison’s in Texas politics and has said he hopes she’ll stay in the Senate. As chairman of the National Republican Senatorial Committee, Cornyn cannot relish the slow march toward a special election at a moment when he’s trying to engineer a minority takeover in November. But he’s not asking her to clarify her plans.

“I think Kay’s frame of mind is that she’s in the race, and she’s running to win, so I don’t think now’s a good time to have that conversation,” Cornyn said in a comment published Sunday in the Houston Chronicle.

Along with Roger Williams and Michael Williams, the list of officially announced candidates includes Elizabeth Ames Jones, also a state railroad commissioner; Florence Shapiro, the state Senate President Pro Tem; and three lesser-known hopefuls.

And looming as possible candidates are other big-name Republicans such as Lt. Gov. David Dewhurst, a wealthy and self-financing politician, and Tom Pauken, chairman of the state Workforce Commission and a former Texas Republican Party chairman.

Hutchison’s vacillation already has spurred some ill will in Austin. She thwarted a domino effect that was expected to follow the resignation she signaled last year, with Dewhurst running for Hutchison’s seat, state Attorney General Greg Abbott running for lieutenant governor and other ambitious Republicans running for Abbott’s open seat.

Instead, Dewhurst and Abbott currently are seeking re-election to their current positions and will be renominated in today’s primary.

“Hutchison is going to lose the primary for governor,” predicted Cal Jillson, a political scientist and veteran Texas elections observer at Southern Methodist University, “and she is going to continue to treat the Senate seat as something that she alone decides what to do with. There will be a growing anger within Republican ranks.”

The Democrats would likely enter a special election campaign as the underdogs, given the state’s strong Republican leanings, but their candidate situation is more clear. John Sharp, the former state comptroller, has been the presumed nominee since December, when Houston Mayor Bill White decided to run for governor.