The GOP scored 33 more seats in the House this election even though Democrats earned a million more votes in House races. Professor Jeremy Mayer says gerrymandering distorts democracy. (The Fold/The Washington Post)

House Speaker William J. Howell, one of Richmond’s most reliable Republican votes, bucked his own party Wednesday to derail a Senate redistricting plan that could have handed the GOP control of that chamber for decades.

Howell (Stafford) used a procedural ruling to kill the new Senate map, resisting pressure from his caucus and Senate Republicans, who assured him that state Attorney General Ken Cuccinelli II (R) was prepared to back the plan.

The redistricting plan drew national attention, and it was lampooned on cable TV because Republicans had muscled it through the evenly divided Senate when a Democrat regarded as a civil rights leader was away attending President Obama’s inauguration. The measure probably would have passed in the House had it gone to the floor for a vote. But as speaker, Howell had the power to make it go away.

He ended 21 / 2 weeks of uncertainty with a procedural move and a few words about how he thinks business ought to be conducted in Mr. Jefferson’s Capitol. “I am committed to upholding the honor and traditions of both the office of Speaker, the institution as a whole and the Commonwealth of Virginia,” he said in a statement.

Howell’s decision angered some Republicans, who privately threatened to block the transportation overhaul that he has been pushing with Gov. Robert F. McDonnell (R). At the same time, Democrats were pleased — and suddenly open to a plan they had shot down just the night before.

An analysis of the Republican proposal to redraw the Virginia state Senate districts.

“We’ll work with the speaker and the House on trying to put together a transportation program,” said Sen. Richard L. Saslaw (D-Fairfax), who added that Howell had displayed “a lot of political courage.”

Senate Republicans said that they were angry but that only Majority Leader Thomas K. Norment Jr. (R-James City) would comment. In a written statement, Norment vowed to push for the redistricting plan in future sessions. The map would have created a sixth majority-black district but would have dispersed black votes elsewhere to make at least eight other districts lean more Republican.

“The entire Senate Republican Caucus is deeply disappointed by Speaker Howell’s unilateral ruling today,” Norment said. “. . . [W]e are confident that the districts approved by the Senate on January 21 will be the districts under which the 2015 elections will be conducted.”

From the moment Howell heard about the new Senate map — he was in a meeting with McDonnell about the transportation plan — the speaker worried that it would become a distraction. He also suspected that the measure was out of order, according to people who spoke on the condition of anonymity to candidly discuss private conversations.

But he did not want to act hastily. So he and his staff pored over 30 years of legislative rulings and turned to the state Capitol’s parliamentary bible: a leather-bound first edition of Thomas Jefferson’s “A Manual of Parliamentary Practice.”

Howell, a Baptist who participates in a Capitol Bible study group on Wednesday mornings at 7, also turned to the real Bible. “Frankly, I think a lot of if it has been reflecting and praying,” a person close to him said.

A wills and estates lawyer who practices in a log cabin, Howell is a stickler for tradition and process. From the start, he questioned whether the map could pass muster. To a bill calling for minor “technical adjustments” to House districts, Senate Republicans tacked on a 36-page floor amendment that redrew Senate lines across the state. That amendment, Howell ruled, was not germane to the original bill.

Only days before the Republicans’ Senate map emerged, Howell ruled against a House Democrat who had sought to pull off a legislative makeover of his own by adding a gun-control measure to an existing bill.

Howell made that ruling on the spot, as he does in most cases. But he felt a need to take his time on this one because the legislation could have a significant effect on both his party and the transportation overhaul he is trying to get passed.

It is not known precisely when Howell made his decision, but he did not announce it to his caucus until Wednesday morning. Hours later, House Republicans met without him to discuss the matter behind closed doors.

After he ruled, an angry Republican legislator said there would be long-lasting implications for Howell’s legislative agenda.

As recently as Sunday, Senate Republican leaders were still pressing their cause in a three-page letter to GOP delegates. They said that they had asked to hold a joint House-Senate Republican caucus meeting to make their case but that their request had been denied.

The letter, obtained by The Washington Post, laid out reasons the districts in the new map were better than the existing ones — splitting fewer jurisdictions, for example — and assuring the delegates that constitutional and election law attorneys had signed off on the plan.

“[W]e additionally consulted with the Attorney General, who has expressed his conviction that the legislation complies with the single object rule, is constitutional, and will withstand legal challenge,” said the letter, from Norment and Sen. Ryan T. McDougle (R-Hanover).

Cuccinelli’s office declined to comment, saying any communication with lawmakers would be privileged. Cuccinelli, who is running for governor, has not taken a public position on the redistricting plan.

McDonnell issued a statement praising the speaker as “an honorable man,” but he declined to take a stand on the merits of his ruling. The governor had criticized the way the map had come through the Senate, but he would not say whether he would veto the measure if it came to his desk.

“The Speaker has exercised his exclusive legislative authority to rule that the Senate redistricting amendments to the House bill are not germane,” McDonnell said.

Republicans said the new map would correct gerrymandered districts that Democrats pushed through in 2011 when they controlled the chamber. Democrats have said the proposed map ran afoul of the state constitution, which specifies that redistricting take place after the decennial census in years ending in one.

In choosing between the two sides, Howell knew he could not please everyone — not even all his House Republican colleagues, who were split on the map.

“You’re running a caucus of 68 people who all got elected individually and who all think they know what’s best,” said Del. David B. Albo (R-Fairfax). “He’s always called germaneness very tight. When in the past . . . I’ve tried to hang transportation amendments onto bills, I’ve been shot down.”

Errin Haines and Fredrick Kunkle contributed to this report.