It’s looking like today is going to signal the end of a once-promising political career in Texas.

I’m still trying to figure out how it got to this point.

Lt. Gov. David Dewhurst has been locked in a form of political mud wrestling with state Sen. Dan Patrick for, yes, Dewhurst’s job as presiding officer of the Texas Senate. The Republican runoff is today and it appears — from my vantage point — that Patrick is going to win this thing.

That means Dewhurst likely is finished as an elected political figure.

This leaves me with terribly mixed feelings.

For starters, I grew to respect Dewhurst immensely in all the years I’d reported and commented on his activities first as Texas land commissioner and then as lieutenant governor.

He came out of virtual nowhere to be elected as land commissioner, taking office in 1999. He hadn’t held any political office. He was a big-time political money man in Houston, where he developed his power base. He ran for lieutenant governor in 2002 and won that race too. He was re-elected twice and then ran for the U.S. Senate in 2012 for the seat being vacated by Kay Bailey Hutchison.

That’s where the trouble began. He got outmaneuvered on the right by Ted Cruz, whose extreme views forced Dewhurst to seek to outflank Cruz on the right — which was virtually impossible. Cruz won the GOP nomination, while Dewhurst went back to work as lieutenant governor.

Now he’s in another likely futile battle.

My respect for Dewhurst grew as I watched him work the Senate. No one could out-detail this guy when it came to the nuts and bolts of legislation. He could talk both of your ears off with legislative minutiae. Indeed, he did that to me on numerous occasions.

However, in this political climate, intimate knowledge of legislation — and an ability to work with members of both political parties — no longer is good enough to stay in public office. You need to be a quick-tongued, fire-breathing sloganeer. That’s what Ted Cruz proved to be in 2012 and what Dan Patrick has demonstrated this year.

Dewhurst has tried to fire back at Patrick — just as he tried against Cruz — but he has appeared clumsy and unsure of himself. That’s not his style.

Patrick won the March GOP primary, but didn’t get enough votes to avoid a runoff. He’s only pushed the pedal harder against the metal in the runoff.

A part of me wants Dewhurst to win, only to demonstrate that there really is value in experience and knowledge. Another part of me is disappointed in the extreme tone he has taken in this campaign to try to counter the relentless attacks by his runoff opponent.

Therein is the source of my mixed feelings about this race.

I’m afraid David Dewhurst’s time on the stage is about to end. Turn out the lights.