By Gabriel Debenedetti
WASHINGTON, March 13 (Reuters) - Democratic senate leader Harry Reid delivered his latest attack on billionaire industrialists Charles and David Koch, saying they were trying to buy the American political system by funding conservative and libertarian candidates in midterm elections.
Reid, 74, repeatedly used the word "radical" to decry the influence on U.S. politics of the Kochs in a speech to the U.S. Senate on Thursday. The brothers spent over $100 million on the 2012 elections and continue to pour money into races for the November midterms in which control of Congress is at stake.
The Nevada senator's bitter jabs appeared to reflect concerns among Democratic leaders over the Kochs' big spending at a time when polls show displeasure over President Barack Obama's healthcare overhaul hurting his ratings, and those of other Democrats.
"These are two oil barons, and they're trying to rig the political system to favor the rich and especially favor themselves," Reid said, marking at least the seventh time in recent weeks he has gone after the Kochs in public.
Through a network of advocacy groups - most prominently Americans For Prosperity (AFP) - the Kochs have put out a range of television and Internet advertisements bashing Democratic House and Senate candidates who support the healthcare law known as Obamacare.
AFP and other Koch groups have spent more than $30 million in this election cycle. Reid's speech was part of a Democratic push to fight back by casting the Koch brothers as villains.
The Democratic Senatorial Campaign Committee (DSCC) has launched a campaign claiming the Republican Party is "addicted to Koch" (pronounced "coke"). The committee has promised to aggressively point out when Koch-backed ads are discredited and to create Web ads and a social media push.
"Senator Reid knows that Republicans are going to pay a price in 2014 for their unshakeable allegiance to the Koch brothers by pushing an agenda that is good for billionaires and bad for almost everyone else in the country," DSCC spokesman Justin Barasky said.
"If the Kochs get their way, they will buy a U.S. Senate that wants to end Medicare as we know it and wants to dismantle Social Security. That's a huge problem for the country."
Democrats have begun releasing television ads targeting the Koch brothers, whom Forbes lists as each having a net worth of about $40 billion.
Senate Majority PAC, a Democratic group, put out an ad in Louisiana criticizing the Kochs' spending in that state's Senate race. Alaska Senator Mark Begich, another Democrat targeted in Koch-sponsored ads, attacked the brothers in a television spot of his own.
Robert Tappan, a spokesman for Koch Industries, fired back at Reid on Thursday, casting the senator as a man who "sounds desperate to keep his job."
Reid is up for election for a sixth six-year term in 2016. Many Republicans are hoping that Nevada's popular governor, Brian Sandoval, will challenge him.
"Like most Americans, we believe his conduct is beneath his office, and his statements about us are false," Tappan said.
"For the sitting majority leader to go out on the floor of the Senate and single out two individuals and try to demonize them because they're exercising their First Amendment rights ... we find that very, very troubling," he added.
DEMOCRATS' BILLIONAIRE "HYPOCRISY"
Democrats' concerns about the influx of major out-of-state donations influencing congressional races were exacerbated on Tuesday when Republican David Jolly won a special election over Democrat Alex Sink in Florida's 13th District.
Both parties and their supporters spent millions of dollars on the race, which was widely seen as an early sign of Democrats' election vulnerability on Obamacare.
For months, Democratic leaders have urged major donors to step up their contributions for the midterm elections. They are concerned Republicans are more focused on the midterms than Democratic donors, who may be looking ahead to 2016, when former secretary of state Hillary Clinton may run for president.
Obama has asked donors to contribute more in a series of fundraisers. Billionaire hedge fund manager Tom Steyer has pledged to spend as much as $100 million on the midterm elections, focusing on candidates who favor plans to curb climate change.
On Thursday, Republicans seized on such efforts in chiding Democrats over Reid's comments about the Kochs. Republican National Committee spokesman Jahan Wilcox pointed to a series of recent speeches by Senate Democrats on climate change, remarks that many Republicans saw as a nod to Steyer.
"The hypocrisy of the Senator Reid knows no end, because a few days ago he rented out the chamber so Democrats could curry favor with liberal billionaire Tom Steyer," Wilcox said. (Additional reporting by Susan Cornwell; Editing by David Lindsey and Andrew Hay)