George Allen fended off three opponents in a rain-soaked, low-turnout primary Tuesday to secure the Republican nod for U.S. Senate in Virginia, clearing the way for a battle against fellow former governor Timothy M. Kaine that could help decide which party holds the keys to power on Capitol Hill.

In the race to succeed retiring Sen. James Webb (D), Allen won the nomination over Chesapeake minister E.W. Jackson, Del. Robert G. Marshall (Prince William) and former Virginia Tea Party Patriots head Jamie Radtke, all of whom argued that he was insufficiently conservative and a poor choice to face Kaine (D) in November. None of the three was able to compete against Allen’s near-universal name recognition and large fundraising edge.

At a crowded victory party in Richmond, Allen called himself “the common-sense conservative nominee” who would create jobs and work to repeal President Obama’s health-care law.

“We want to send a message to the world that America is open for business again,” Allen said. “We envision a better future than what we are enduring today.”

Kaine quickly made clear how he would run against Allen in their head-to-head matchup.

“Voters already had the chance to experience George Allen’s vision during his last term in the Senate, which turned record surpluses into massive deficits, added trillions to our debt, and put opportunity for a select few ahead of opportunity for all our businesses and families,” Kaine said in a statement Tuesday night. “George Allen’s approach helped create our economic mess; Virginians can’t afford six more years.”

With 99 percent of precincts reporting, Allen had 65 percent of the vote. Radtke was running second at 23 percent, Marshall had 7 percent and Jackson 5 percent.

In Northern Virginia, Rep. James P. Moran beat back a Democratic primary challenge from Navy veteran Bruce Shuttleworth by a wide margin, while retired Army Col. Chris Perkins defeated traffic engineer Ken Vaughn for the Republican nomination to face Rep. Gerald E. Connolly (D).

Tuesday’s Senate result cements a matchup both parties have expected for 14 months, since Kaine announced he was leaving his post as Democratic National Committee chairman to enter the race. Polls have consistently shown a tight contest, one of a handful that will determine whether Democrats can maintain control of the Senate.

The contours of the general election contest between the two well-known, well-funded Virginians looked clear before the primary made it official.

For Allen, the race represents a chance at redemption after his dramatic reelection loss to Webb in 2006. Allen appeared to have that contest well in hand — and was already mulling a run for president in 2008 — when he referred to an Indian American volunteer for the Webb campaign as “macaca,” an ethnic slur in some cultures.

Allen’s support steadily eroded after that, leading to his Election Day loss to Webb by fewer than 10,000 votes out of 2.3 million cast. Since then, Allen has worked as a consultant while giving speeches, authoring a book and awaiting his chance to make a comeback and put the Senate seat back in the red column.

For Kaine, the contest marks a return to state politics following a detour to serve as Obama’s DNC chairman. Rising from the Richmond City Council to become the city’s mayor, then lieutenant governor and governor, Kaine sought to craft a reputation as a moderate willing to work with both sides of the aisle, in the mold of his longtime friend, Sen. Mark Warner (D).

By taking the DNC post, Kaine opened himself to attacks from Republicans that he is now too partisan and too closely identified with controversial policies of the Obama administration to reclaim the centrist mantle.

Kaine has focused much of his campaign message on cultivating Virginia’s “talent economy” by improving the state’s educational system and job-training programs. Allen has emphasized the need for lower taxes, less regulation of business, and increased domestic production of coal, oil and natural gas.

At Lake Anne Elementary in Reston on Tuesday, Frank Carlson said he supported Allen because he was impressed with Allen’s history as governor.

“He’s a moderate, and he’s a good man,” Carlson said. “It wasn’t a hard decision.”

Carlson added that he doesn’t like the tea party and has been alarmed by its rising role in national politics.

At Rivers Edge Elementary School in Glen Allen, north of Richmond, Jeanne Nugent, a 42-year-old costume designer, said she voted for Radtke. “I think she stands for what real family values are all about,” Nugent said, referring to the former tea party leader’s focus on getting federal spending under control.

On the House front, Perkins will face a difficult campaign against Connolly, whose fortunes have improved since he defeated businessman Keith Fimian (R) by less than 1,000 votes in 2010.

The new congressional district map made all of Northern Virginia’s incumbents safer, including Connolly, whose seat lost some Republican-leaning portions of Prince William County and picked up more hospitable territory along the Dulles Toll Road.

Unlike in 2010, Connolly will probably benefit from having Obama atop the ticket to boost Democratic turnout. And the incumbent had a campaign war chest of $1 million as of May 23, while Perkins had $60,000.

At Robinson Secondary School in Fairfax County, Walter Bajkowski, a government IT contractor, said he voted for Allen and Perkins.

“I like George Allen from before — his philosophies and what he works toward,” Bajkowski said. “I was satisfied with what he did.”

And Bajkowski opted for Perkins over Vaughn because of his personal story.

“He’s retired military, family guy,” Bajkowski said.

Elsewhere in the state, Republican Reps. Eric Cantor, Randy Forbes and Robert Goodlatte all defeated primary challenges with ease.

Tuesday’s turnout appeared to be dampened by morning rain in much of the state, and by confusion over the fact that Virginia held its presidential primary in March. In the days leading up to the vote, many residents told candidates they thought the congressional primary had already happened.

“People don’t even know there’s an election today,” said Robert Strange, precinct chief at Alvey Elementary School in Haymarket.

By 4 p.m. at Robinson, only 178 voters had cast ballots, or about 4 percent of the precinct’s approximately 4,600 registered voters. James D. Emery Jr., the precinct’s chief election officer, said it was lighter than the March presidential primary.

“It’s surprising,” Emery said. “I don’t know that we’re going to make 5 percent.”

At Loudoun County High School, precinct officials were eagerly awaiting their 10th voter of the day, who had not yet arrived by 1 p.m. Election volunteer Donna Darnes said she blamed a combination of bad weather and minimal outreach.

“Usually the streets are lined with signs,” she said. “There’s practically nothing around here.”

At Albert Hill Middle School in Richmond, voting was so light that one poll worker appeared to be snoozing late Tuesday morning while another had her nose in a book plucked from the school library shelves. Only 18 voters had been in by 11 a.m.

Election officer Joyce Trickett, 68, had the foresight to bring a leather-bound book, “English History” by D.H. Montgomery, from home.

“I’m up to the Norman Conquest,” she said.

Staff writers Jeremy Borden, Caitlin Gibson, Anita Kumar, Fredrick Kunkle and Laura Vozzella contributed to this report.