There is an interesting political story unfolding right now in Texas. And it's not about Gov. Rick Perry (R) or state Sen. Wendy Davis (D).

We're talking about Lt. Gov. David Dewhurst (R). Once a promising prospect for higher office, Dewhurst is now in a primary fight to keep his job against a trio of Republicans who have taken aim at his handling of a legislative debate over abortion that has captured national attention.

"His future includes a very tough race for reelection," said veteran Texas Republican strategist and lobbyist Bill Miller.

The stakes couldn't be higher for Dewhurst in the current push to tighten abortion restrictions in the Texas legislature. As president of the state Senate, Dewhurst presided over what for Republicans was an embarrassing end to the last legislative session. Davis and a flood of protesters stymied an abortion bill that Dewhurst urged Perry to add to the legislative agenda.

State lawmakers are currently revisiting the bill in a special session, and it is expected to pass. But the episode was yet another setback for Dewhurst, whose prospects for career advancement once looked bright, but is now fighting to tread water.

“I know it’s harder to stay on top than to get on top,” Dewhurst recently told the Dallas Morning News, when asked about his reelection campaign. “I’m going to make sure this state keeps moving forward. I’m going to help keep Texas No. 1.”

It's a striking turn of events. In the summer of 2011, Dewhurst officially announced his bid for retiring GOP Sen. Kay Bailey Hutchinson's seat. He did so from a powerful political perch with deep ties to influential Republicans and the ability to raise big bucks and chip in millions more from his own pockets.

For a while, Dewhurst seemed poised for victory. A January 2012 internal poll showed Dewhurst up 45 points on Ted Cruz, then a little-known former state solicitor general running as the tea party alternative to the lieutenant governor.

But Cruz slowly picked away at Dewhurst's lead, built a national tea party following, and eventually felled the onetime frontrunner, registering what was arguably the biggest upset of the 2012 cycle.

Nowadays, Cruz is a conservative agitator in the Senate who might run for president in 2016. And Dewhurst is in another tough campaign back home.

State Sen. Dan Patrick (R) recently announced he will try to unseat Dewhurst. Patrick is a conservative radio show host who backed Dewhurst's Senate campaign. He joined state Land Commissioner Jerry Patterson and state Agriculture Commissioner Todd Staples, who had already announced campaigns for lieutenant governor.

And all three have sought to blame Dewhurst for what happened with the abortion bill.

"Patrick’s entry makes it highly unlikely that any candidate can win without a run-off," Miller said, referring to the law in Texas that mandates runoff elections if no candidate receives a majority of the vote on the first ballot. "And run-offs in Republican primaries favor the more conservative candidate and it is arguable who that may be."

A recent survey conducted by Democratic automated pollster Public Policy Polling showed Dewhurst with a 20-point lead over Patrick, his nearest competitor. But Dewhurst was well below 50 percent in the poll. And only about two in 10 Texas voters rated him favorably.

Texas Republican strategist Suzanne Bellsnyder said Dewhurst's opponents will present him with a tough test, but he still has the advantage.

"I give the edge to Dewhurst despite his failed Senate race, for two reasons," wrote  Bellsnyder in an e-mail. "One, The 'Tea Party' faction of our party has been less successful in moving candidates at the state level far to the right. ... Second Dewhurst is an incumbent and will do a better job this go around talking about his RECORD on job creation, investments in infrastructure and education, and reining in state spending. These issues will have large appeal with voters who turn out for state races."

Dewhurst spokesman Travis Considine said the lieutenant governor "is focused on passing this pro-life legislation and finishing his priorities, topping off what has already been one of the most conservative legislative sessions in decades in Texas."

Dewhurst wields a lot of power as lieutenant governor of Texas, and it's far too early to close the book on his career. But his trajectory is a reminder of how quickly things can change in politics.