Virginia Lt. Gov. Bill Bolling (R) (Tracy A. Woodward/The Washington Post)

The question hangs on whether Lt. Gov. Bill Bolling (R), who has the power to break tie votes in the chamber, can vote on everything that comes before the 40 senators — including the budget and key matters that determine committee assignments. The Republicans says yes. The Dems say no.

So what happens Jan. 11, when the Senate is gaveled into session?

The GOP says it’ll be in charge.

But as recently as last week, when Gov. Robert F. McDonnell (R) unveiled a budget that shifts sales tax revenue around in ways Democrats weren’t too keen on, Sen. Donald McEachin (D) said his caucus will challenge any votes from Bolling on the budget and other matters that they contend are the exclusive right of elected senators.

“I think as long as the governor’s sales tax proposal moves education [revenue] to transportation, that budget will not receive 21 votes in the Senate,” McEachin said. “The constitution clearly says you have to have a majority of members elected [to the Senate]. It will not get 21 votes in the Senate.”

McEachin, the Democratic Caucus chairman, would not say just what the Democrats would do if and when Bolling casts those votes. But he’s not done with a lawsuit he brought to challenge Bolling’s voting authority, despite a Richmond judge’s decision this month not to issue a temporary injunction in the case.

“The suit’s still pending,” McEachin said.

In a recent interview, Democratic Party Chairman Brian Moran sounded less inclined to bank on the courts than on the ability of the two parties to work out a power-sharing deal.

“Ultimately, we would hope they [Republicans] would feel sufficient public pressure to come to the table and resolve this impasse,” Moran said.

Stay tuned.