Like a pack of conniving relatives whispering around the deathbed of a rich man, Texas senators and political strategists are closely watching Lt. Gov. David Dewhurst’s bid for the U.S. Senate and Gov. Rick Perry’s bid for the presidency.

If both leave Texas, the Senate will choose their replacements. If only one wins, senators will pick a new lieutenant governor either way. (Dewhurst would automatically move up if Perry wins the presidency.) The timing of those selections — which comes down to who’s voting and who isn’t — is crucial to the outcomes.

The immediate question is whether five current state senators or their successors will be voting to elect the successor to Dewhurst. Four Republican incumbents have announced they won’t seek re-election, so we know they’re short-timers. Another, Sen. Wendy Davis, D-Fort Worth, has been redistricted into hostile territory; purely by the numbers, her chances of winning re-election as a Democrat are small.

Play it out. Davis’ successor would be a Republican, i.e., more conservative. The favorites to replace Steve Ogden, Mike Jackson and Florence Shapiro, all Republicans, are each more conservative than the incumbents. Chris Harris is likely to be replaced by a Republican, too, but no favorite has emerged.

Who gets to vote on the successors is a matter of timing. The Senate has to convene to choose a new lieutenant governor — and if need be, a new governor — within 30 days of an opening. They can act faster, but must act within a month. If Dewhurst resigns before the new senators are sworn in — federal legislators take their oaths several days before state legislators do — the current senators could be the ones doing the choosing. If he leaves office more than 30 days before the Legislature convenes, the incoming senators won’t even have an argument to make, because the current Senate will have to convene and choose.

It’s always difficult to lay these things out with any certainty. For one thing, there’s not much precedent. When George W. Bush resigned in December 2000 and Perry ascended, the Senate chose Bill Ratliff, R-Mount Pleasant, to be lieutenant governor, and the membership of the Senate wasn’t an issue. He was picked by the full Senate, using secret ballots.

The easiest way to win an election is to have the votes. The next easiest way is to change the rules of the election. There’s always cheating, but that’s another story.

The new Senate map (which is being challenged in federal court and could change) was drawn to elect 20 Republicans to the 31-member Senate. The majority of the Senate is not from the conservative wing of the Republican Party. That’s true in the current Senate and will most likely be true in the next one, even with five or more fresh faces. They simply don’t have the votes if it’s up to the full Senate.

They could reach a majority in the Republican caucus, however, where it takes 11 to prevail. If the Republicans agree to stick with the caucus decision, they’d have a majority in the full Senate. The outcome of the caucus vote would depend on who’s in the Senate when that vote is taken — new folks or old ones.

If the Senate’s vote is open — if the public can see how each senator votes — it becomes easier for outside groups to influence the senators. Some are already working on that. Michael Quinn Sullivan, with a group called Empower Texans, is trying to get conservative activists to work on their senators now, more than a year before this unfolds, to force an open ballot. “If people are concerned, they need to talk to those senators today,” he said.

Even if that doesn’t get them the lieutenant governor they want, it’ll make the autopsy easier when conservatives are marking senators as friends and enemies. The theory is that the Republican senators (and even some Democrats) might vote differently if the rest of us can see how they’re voting. Sen. Dan Patrick, R-Houston, and Sullivan think that will benefit their side — so much so that each says the open vote is more important than an agreement to vote in and stick together as a caucus.

“I want the outside to impact the inside,” said Patrick, who’s been working to push the vote into caucus and to make it a public ballot. “It should not be an inside game. That’s what people hate about politics.”

Of course, Perry and Dewhurst could lose and return to Austin for another two years. That rich man could hop out of his deathbed.

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