Argument: Unlimited spending allows special interests to dominate elections
President Barack Obama said in his 2010 January State of the Union address: "With its ruling today, the Supreme Court has given a green light to a new stampede of special interest money in our politics. It is a major victory for big oil, Wall Street banks, health insurance companies and the other powerful interests that marshal their power every day in Washington to drown out the voices of everyday Americans. This ruling gives the special interests and their lobbyists even more power in Washington--while undermining the influence of average Americans who make small contributions to support their preferred candidates. That's why I am instructing my Administration to get to work immediately with Congress on this issue. We are going to talk with bipartisan Congressional leaders to develop a forceful response to this decision. The public interest requires nothing less."
Sen Russell Feingold (D-WIS.): "Co-author of the McCain-Feingold campaign finance legislation. The Massachusetts election Tuesday was the last one conducted under rules that had been in place for over a century to protect the right of the people to choose their government free from enormous expenditures of corporate wealth. Next time voters want to send us a message at the ballot box, they may find their voices drowned out by wealthy corporations with their own special-interest agendas.
This Supreme Court decision takes us back a century to a legal framework that fostered a golden era of corporate influence. While the core of the McCain-Feingold law ¿ the ban on unlimited "soft money" contributions by corporations, unions and wealthy individuals directly to the political parties ¿ remains intact for now, the reasoning of this decision undermines the foundation of a host of laws enacted to strengthen our democracy and curb corruption in government. Indeed, the soft-money ban could very well be the next target of those who want to see our political system dominated by corporate influence.
This decision gives a green light to corporations to unleash their massive coffers on the political system. The profits of Fortune 500 companies in 2008 alone were 350 times the entire amount spent on the last presidential election." 
Greg Palest. "Manchurian Candidates: Supreme Court allows China and others unlimited spending in US elections." OpEdNews. January 23rd, 2010: "We've been there. The 1994 election brought Newt Gingrich to power in a GOP takeover of the Congress funded by a very strange source.
Congressional investigators found that in crucial swing races, Democrats had fallen victim to a flood of last-minute attack ads funded by a group called, "Coalition for Our Children's Future." The $25 million that paid for those ads came, not from concerned parents, but from a corporation called "Triad Inc."
Evidence suggests Triad Inc. was the front for the ultra-right-wing billionaire Koch Brothers and their private petroleum company, Koch Industries. Had the corporate connection been proven, the Kochs and their corporation could have faced indictment under federal election law. As of today, such money-poisoned politicking has become legit."
Fred Wertheimer. "Turning clock back 100 years, decision will corrupt government." The Atlanta Journal. January 27, 2010: "The Supreme Court decision in the Citizens United case is a disaster for the American people and a dark day for the Supreme Court.
The decision will unleash unprecedented amounts of corporate “influence-seeking” money on our elections and create unprecedented opportunities for corporate “influence-buying” corruption.
The decision is the most radical and destructive campaign finance decision in Supreme Court history. In order to reach the decision, five justices abandoned long-standing judicial principles, judicial precedents and judicial restraint."
Fred Wertheimer. "Turning clock back 100 years, decision will corrupt government." The Atlanta Journal. January 27, 2010: "The Supreme Court majority has acted recklessly to free up corporations to use their immense, aggregate corporate wealth to flood federal elections and buy government influence. The Fortune 100 companies alone had combined revenues of $13 trillion and profits of $605 billion during the last election cycle.
Under the decision, insurance companies, banks, drug companies, energy companies and the like will be free to each spend $5 million, $10 million or more of corporate funds to elect or defeat a federal candidate — and thereby to buy influence over the candidate’s positions on issues of economic importance to the companies.
The decision turns back the clock to the 19th century, eliminating a national policy to prevent the use of corporate wealth to corrupt government decisions — a policy that has existed for more than a century."
"A Bad Day for Democracy". The Christian Science Monitor. January 22, 2010: "Thursday was a bad day for democracy. The Supreme Court’s decision in Citizens United v. the Federal Election Commission paves the way for unlimited corporate and union spending in elections, and the drowning out of the average citizen’s voice in our public policy debates. In other words, the court has made a bad situation worse by enhancing the ability of the deepest-pocketed special interests to influence elections and the US Congress."
Benjamin L. Ginsberg, a Republican campaign lawyer at the law-and-lobbying firm Patton Boggs who has represented both candidates and outside groups, including Swift Boat Veterans for Truth, a group formed to oppose Senator John Kerry’s 2004 presidential campaign: "It will put on steroids the trend that outside groups are increasingly dominating campaigns."