SPRINGFIELD, MO. • Republican Roy Blunt soundly defeated Democrat Robin Carnahan to become Missouri's next U.S. senator in a bruising battle between two of the state's most prominent political families.

The results signaled voter frustration with the sluggish economy and with the direction of the country under President Barack Obama, who, two years after winning office, will have to work with new lawmakers who campaigned on opposing White House policies.

Blunt's decisive victory was part of a larger pro-Republican trend statewide. GOP challenger Tom Schweich defeated incumbent Democrat Susan Montee in the state auditor's race, while longtime 4th District incumbent U.S. Rep. Ike Skelton lost to Republican challenger Vicky Hartzler. Also, Republicans looked to increase their majorities in both chambers of the Missouri Legislature.

Blunt, in a victory speech in his hometown of Springfield, Mo., promised to fight for more jobs and decreased government spending.

"I'm honored to get the chance to work for you," Blunt, 60, said. "This is the time where we're going to decide if we're going to renew the lease on freedom."

As he has done in every one of his congressional elections, Blunt ended his campaign with a Republican event in Cassville the night before the election. The 14-year congressman credited his Senate win with an ambitious schedule that took him to every one of Missouri's 114 counties at least once. Blunt bragged of making more than 900 campaign stops, including 50 in the last week to help rally already excited Republican voters.

Blunt secured victory with a strong showing in suburban St. Louis and Kansas City. He dominated the state's rural areas, which typically vote Republican.

His victory ends a long and acrimonious campaign that began when retiring U.S. Sen. Christopher "Kit" Bond, who took over for Tom Eagleton in 1987, announced his own retirement early last year.

Carnahan and Blunt raised more than a combined $20 million, much of it spent on blistering commercials attacking the opposing candidate.

Blunt also benefited from a round of ads from third parties, which were better able to flex their spending muscle since a January Supreme Court decision gave them greater latitude to participate in campaigns.

Blunt effectively linked his opponent to Obama - who, polls showed, had an approval rating in Missouri below the national average - repeatedly using images of the president with Carnahan at a Kansas City fundraiser.

The strategy of making the election a referendum on the president registered with voters.

"I've never had such bad feelings for any administration," said Blunt voter Floyd Wright, 66, of Huntleigh, who operates a trucking business. "I've been in business 40 years. I've seen bad times and good times. This is about the toughest I've ever seen it."

Mike Tettamble, 74, of south St. Louis County, called Carnahan an "Obama clone." Tettamble bemoaned that, after two years of Obama in the Oval Office, the country remains mired in economic uncertainty.

"And we just keep getting into it deeper and deeper and deeper," Tettamble said.

Carnahan sought to paint Blunt - who is married to a lobbyist and was his party's chief vote counter in Congress - as a "Washington insider," but the strategy never gained traction with voters.

Initially, the Senate contest was billed as a battle of political heavyweights, featuring two candidates with broad name recognition and deep family roots in Missouri politics, where close elections are the norm.

Instead, the suspense waned as it became increasingly clear that Carnahan would have difficulty countering Republican momentum in a state that Obama lost by a narrow margin in 2008. The race gradually dropped from the national radar, as Carnahan was unable to make up a deficit in polls that only grew larger as the leaves changed colors.

Ten years ago, Carnahan's father, former Gov. Mel Carnahan, won a Senate election posthumously after he was killed in a plane crash weeks before. Carnahan's mother, Jean, was appointed to the seat.

Joined by her family on stage at an election gathering in downtown St. Louis, Carnahan said she is more optimistic now about the prospects facing the state and nation than when she began the campaign.

"Despite all of these hardships, Missourians understand that we've faced tougher times before," Carnahan, 49, said. "My sense is that folks are ready to make a shared sacrifice to do what we need to do to get our country back on track."

Carnahan urged her supporters to remain "engaged" and "defiant."

"And, above all, you never, ever let the fire go out," Carnahan said, a reference to a line she uttered a decade ago in a eulogy for her father.

Blunt, a fifth-generation Missourian born in a doctor's office in tiny Niangua, Mo., heads back to Washington as the father of a former governor, and the son of a former state lawmaker.

Though Carnahan's family background and experience away from Washington made her an attractive candidate for Democrats, the political atmosphere favored Republicans too much for her to win, said Steven S. Smith, political science professor at Washington University.

"Is there anything Carnahan could have done about it? Could she have run further and faster away from the national Democrats? I'm not sure," he said. "It's hard to do that, and yet generate enthusiasm from your base."

History has shown that midterm elections are typically a tough year for either party after taking control of the White House.

While Republicans elsewhere were buoyed by the Tea Party movement, Blunt weathered a lukewarm relationship with the group. Some Tea Party supporters backed another Republican, state Sen. Chuck Purgason, in the August GOP primary.

Any Republican divisions, however, were not evident in Tuesday's results, which saw Blunt with broad support throughout the state.

For Blunt, the Senate victory marks the most notable achievement in an up and down political career.

Blunt, a former teacher and university president, was Missouri secretary of state for eight years, though his bid to become governor ended in the 1992 primary - a year in which Mel Carnahan won the general election.

In 1996, Blunt was elected to Congress, where he quickly shot up the ranks of Republican leadership.

But his ties to former House Majority Leader Tom DeLay - now facing money laundering charges in Texas - cost him within his party. In 2006, he lost an election to become majority leader to Ohio Republican John Boehner, who is now in line to become the next speaker of the House.