The sparring began quickly over the exact meaning of a tie.

A day after Virginians appeared to have elected a pair of new GOP senators, Democrats and Republicans disagreed about what Tuesday’s GOP gains mean for control of the state Senate.

If Tuesday’s election results hold, the Senate would have 20 Republican members and 20 Democratic members.

Republicans said a Republican lieutenant governor — Bill Bolling — who constitutionally would cast the deciding ballot in any tied vote allows them to take control of the evenly split chamber.

Democrats did not agree.

Republicans picked up one seat in Southside Virginia and declared victory in a second race south of Fredericksburg, where the GOP candidate led by less than half a percentage point.

Senate Majority Leader Richard L. Saslaw (D-Fairfax) said Republicans might have the authority to take control, but he cautioned against their acting too hastily. “We still can’t lose sight of the fact that one of these races will probably have to go to a recount,” he said. “It’s not over yet.”

Sen. J. Chapman “Chap” Petersen (D-Fairfax) pointed to precedent: In the 1990s, the last time — and the only time — the chamber was evenly split, the two sides shared power, meaning they shared committee chairmanships and other responsibilities. If the GOP seized power, he said, the Democrats could sue.

“The lieutenant governor is not a member of the Senate,” Petersen said. “To me, if it’s 20-20, it’s 20-20.”

If Republicans were to take hold of the Senate, they would hold the governor’s mansion and both chambers for only the second time since the Civil War. In the 100-member House of Delegates, they now hold a hefty 68-seat majority — the highest in Virginia history.

“We are thrilled with the results of last night’s election,” Gov. Robert F. McDonnell (R) said Wednesday at a news conference on Capitol Square. “I am delighted to say Republican leaders in the House and Senate have been entrusted with the privilege of governing.”

Democrats still held out hope that Sen. R. Edward Houck (D-Spotsylvania) could win his race against Republican Bryce Reeves, as local election officials met Wednesday to count provisional ballots and review calculations and tapes from voting machines and other records for errors.

But after such an initial canvas, Reeves’s lead actually grew — from an 86-vote margin to 224 votes.

“The race for this seat remains too close to call,” said Craig Bieber, Houck’s campaign manager. “There were several significant discrepancies during Tuesday night’s tabulation that deserve further attention during the canvassing and certification process.”

At one point, the state had Houck carrying a Spotsylvania precinct by 140 votes, but it was later discovered that Reeves actually won the precinct, Bieber said. He said he did not doubt that Reeves won that location but wonders whether other errors ultimately would be resolved in Houck’s favor.

“We are still hearing from people,” Bieber said. “There were discrepancies.” He declined to elaborate, saying it would be premature.

But the Reeves campaign wasn’t holding back. “Reeves Elected Senator,” said the headline on a news release issued by his campaign before midnight Tuesday.

“We’re happy to be where we’re at,” said Reeves’s campaign manager, Chris Leavitt. “We know we need to go through this process and continue to cross our T’s and dot our I’s.”

About 100 to 150 provisional ballots were cast in the 17th Senate District race, according to State Board of Elections Secretary Donald Palmer. The results of the canvass will be forwarded to the Board of Elections, which will review the results and certify them Nov. 28.

After that, a candidate has 10 days to petition the Circuit Court in his home county for a recount.

There are no automatic recounts in Virginia. But a candidate who has lost by a margin of 1 percent or less may request one at his own expense.

If the margin is 0.51 percent or less, the local jurisdiction pays for the recount. If Wednesday’s tallies ultimately are certified, the difference in the Houk-Reeves race is exactly 0.5 percentage points.