Lawmakers were hoping to get out of Austin with their business done, without the prospect of a special session this summer.

Fat chance.

Sen. Wendy Davis, D-Fort Worth, filibustered for a little more than an hour Sunday night, probably killing a school finance and revenue bill critical to the budget (it's still possible for a four-fifths supermajority of the Senate to pull it up for a vote today). And the House hit a midnight deadline without approving three major pieces of legislation — including one that's designed to corral Medicaid costs and help balance the state budget.

Gov. Rick Perry had promised earlier in the day to call lawmakers back on Tuesday if the budget bills weren't all approved. The regular session ends today, and it looks like the first special session will begin as early as tomorrow morning.

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Even without an unfinished 2012-13 budget to bring them back, Gov. Perry had already set the table for a special legislative this summer.

• The governor, tort reformers, trial lawyers and lawmakers in the House and Senate couldn't put together a fix to the Texas Windstorm Insurance Association in the 140-day legislative session, and Perry promised that if they didn't get it done he'd call them back to Austin in July to finish up.

When they hit the deadline at midnight Saturday, they didn't have anything except for the governor's promise that they'll be back.

• Lawmakers completed their work on new political maps for the State Board of Education and for the Legislature itself, but never even presented or held hearings on maps for congressional redistricting. Perry's aides indicated for weeks that their boss would be unlikely to call lawmakers back for that purpose alone. Then, in the last days of the session, the governor told reporters he'd be willing to call a special session on congressional maps if House and Senate leaders can show him they've got enough votes to make it a quick deal.

Whether or not the governor is thinking about a presidential race, the memory of Senate Democrats running off to Albuquerque — as they did in the 2003 redistricting fight — has to make him wary of a session on that all by itself.

• Then there is the sanctuary cities legislation, one of six items the governor put on a list of legislative "emergencies" to speed consideration by the House and the Senate. That one didn't make it out, and a special session could give him another shot at it.

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On Sunday, they added to their troubles when the midnight bell tolled before the House had approved three bills that created interstate health compacts, contained Lt. Gov. David Dewhurst's health reforms, provided funding for textbooks, and addressed efficiency in the Medicaid program. That last bill is one of several considered critical to the budget.

If the past is any guide, a special session that starts with one topic often picks up others along the way, and Perry could add other issues — new ones or things left undone during the regular session, small issues or large ones — as he goes along. Lawmakers will likely start with the budget bills on Tuesday, and if they can come up with negotiated solutions on others — redistricting, for instance — Perry might add those to the agenda.

Rep. Charlie Geren, R-Fort Worth and the chairman of the House Administration Committee, told fellow legislators this week that he started the regular session by budgeting for two special sessions, either on the state budget or redistricting or whatever else might go haywire.

Perry has said in the last few weeks — possibly to spur lawmakers to finish — that he didn't see any reason for a special session. Aides said he didn't particularly want one. But in the last few days, budget talks careened from hopeful to hopeless and other issues, like TWIA, ran out of time for more negotiation.

The governor had no need to threaten overtime on the budget — everybody in the building has known the budget has to get done, and that it would go down to the wire — for most of the session.

Threatening a special on TWIA made it easier for opponents of the budget and of proposed school finance changes to tap the brakes. They weren't solely to blame for causing a special session — it was going to happen anyhow, according to the governor — and it eased the tension about extra innings as the vote on a critical last piece of the budget puzzle approached.

For whatever reason, the state's budget writers worked up until the final deadlines, into the part of a legislative session when a small procedural delay can be fatal to a bill. In the House, that bill — SB 1811 — didn't come up for debate until six hours before its end-of-session deadline. But the House turned out not to be the obstacle; that was the Senate, where the bill came up for consideration only two-and-a-half hours before the deadline.

The timing, and the TWIA wreck, also played in favor of legislative Democrats. They don't get blamed for a special session that was going to happen anyway. They got a chance to push the school finance fight into the summer, when the schools are closed, and when teachers and other school workers have time to come to the Capitol to talk to their elected representatives. And they got an opportunity — if the governor is serious about "thinking about" a presidential race — to disturb his speculation. Perry can still duck all of that, but only if the special session is quick and relatively quiet.

Could be quite a summer.

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