CHARLESTON, W.Va. - Lawmakers returning to the state Capitol Tuesday know the budget is their first priority, but beyond that it's partially a mystery as to how they'll spend the next 10 days or so.

There's plenty of speculation about what a special session agenda called by Gov. Joe Manchin might look like, but one of the duties they'll almost certainly be handling involves revisiting bills vetoed by Manchin since the regular session ended in April.

House Speaker Rick Thompson plans to bring up the vetoed bills as early as Tuesday, according to spokeswoman Stacey Ruckle, and the Legislature will have the governor's blessing for most of that work.

Most of the bills Manchin has vetoed have been for what are called technical reasons -- a bill's title might not reflect an important amendment, for example, or a typo would make the bill address the wrong section of state code.

With those errors in place, the bills can't become law, so Manchin vetoes them. Generally, in his veto messages he urges lawmakers to fix the mistakes and send them back to his desk.

That's not always the case -- four of his veto messages lack the encouraging language, including measures that would make escaping juvenile justice facilities a misdemeanor and require a now-defunct commission to study carbon capture methods.

Manchin is particularly keen on one bill scrapped by a technical flaw, because it's one of his own. The House of Delegates and the Senate passed his initiative setting benchmarks for utility companies to use more alternative and renewable energy sources, but a legislative mistake derailed it.

Legislative clerks reviewing the work of the session about two weeks after it ended found that not all the House amendments were attached to the bill document when it was handed to the Senate for final approval.

That means the bill never actually passed.

"That will definitely come back up," Manchin spokesman Matt Turner said. "That's something that obviously he's going to put on the agenda."

While lawmakers have pushed for a number of measures to be included, the special session's work will largely be Manchin's responsibility.

"A lot of it is in the governor's court, to be quite frank," said House Minority Leader Tim Armstead. "A lot of it depends on how willing the governor is to share what he has in mind for this special session ahead of time."

Republicans want to see tax reduction measures that died in the regular session be revived, along with a bill that would set a referendum vote on a constitutional amendment banning same-sex marriage in West Virginia.

"That's a vote that can be done quickly," the Kanawha County Republican said. "It doesn't have to be drawn out."

That measure got little support among Democrats during the regular session, though, and contentious issues could prolong the session.

House Health and Human Resources Chairman Don Perdue thinks lawmakers may be in for a long session, and sees evidence for that in what he calls a sped-up approach to the budget.

"There's going to be some contention, and maybe that's why they're fast-tracking the budget," the Wayne County Democrat said. "We may be in special session longer than anyone wants us to be."

Perdue thinks there could be as many as 20 items on the call for the special session, but even in that case, he says the Legislature needs to take more time on the budget.

"The whole thing is moving a little too quickly to get everything fully vetted and I wish we would slow down a little bit," he said.