When Corey Stewart was running for governor of Virginia this year, he pledged to be a fiscal conservative who would block tax increases, tackle the tough task of cutting government spending, and oppose special interests seeking favors.

"At campaign time phony conservatives promise not to raise taxes, but they quickly betray their promises when the special interests come calling," Stewart claimed in one press release.

Stewart lost in the primary by a narrow margin, but the chairman of the Prince William County Board of Supervisors still has a chance to show off his fiscally conservative bona fides later this summer when he votes on what might possibly be largest public subsidy for a minor league baseball stadium in the nation's history.

The proposed stadium to be built off I-95 near Woodbridge for the Potomac Nationals, the single-A affiliate of Washington, D.C.'s major league team could end up costing Prince William County taxpayers more than $35 million.

And Stewart, you see, despite all his principled conservative and special interest fighter talk, has championed the stadium deal since it was first proposed in 2012. He voted with the majority of the board in March to give preliminary approval to the project. At a meeting last week, the board voted to block a proposed referendum on the stadium that would have given county residents the chance to express their opinion directly. Final approval of the project is expected in mid-July.

Unless Stewart and a board majority have a considerable change of heart, taxpayers will be on the hook for construction costs and about $7 million in planned infrastructure upgrades around the stadium.

The team will lease the stadium from the county and the county will have to lease the land for the stadium project from a private developer, JBG Companies. PotomacLocal.com reports that the annual rent payment of $450,000 would be the most expensive in all of minor league baseball.

"That's $17 million over 30 years to lease the property. If we bought it outright, it would be vastly less expensive," Supervisor Peter Candland, one of two county board member to oppose the project during March's preliminary vote, told PotomacLocal.com.

Advocates for the project insist the lease payments will eventually (over 30 years) cover the construction costs. As David Boaz, executive vice president of the Cato Institute, pointed out last week (in a wide-ranging and very effective take-down of crony stadium deals), that's a little bit like saying "I will gladly pay you Tuesday, 30 years from now, for a hamburger today."

To help move things along, Potomac Nationals' owner Art Silber told The Washington Post last week he'd sell the team if Prince William County doesn't pony up the necessary cash. And he played the oldest trick in the get-the-taxpayers-to build-you-a-stadium book, suggesting the new owners might relocate the team.

An economic analysis of the project suggests that it would create 288 jobs and generate $4.9 million in tax revenue over 30 years. Projections like these for stadiums are notorious for their unreasonable optimism. The same report also warns that the Nationals may struggle "to generate the projected revenues," potentially jeopardizing the plan to reimburse the county for the construction costs over the next three decades. If the team can't fulfill those obligations, taxpayers would be left holding the bag, Candland told the Post.

"If the Potomac Nationals or the Silber family wants to sign a guarantee and say they'll backstop it and they won't push it onto the taxpayers, then that completely changes things," Candland said. "But they're not willing to do that."

The Potomac Nationals' stadium plan amounts to a massive government-funded giveaway to a privately owned baseball team, the sort gubernatorial candidate Corey Stewart would have railed against. It remains to be seen whether county supervisor Stewart has the will to keep the taxpayers' best interest in mind.