Americans who contribute to candidates or causes expect a return of some kind on their investment, estimated to total as much as $4 billion this year. But the vast majority of Americans — those who don't make six-figure salaries or run major corporations — are unlikely to be the beneficiaries.

Our political system increasingly benefits the rich and powerful. That's evident in the income gap that has grown over the last three decades and has intensified during the Great Recession. A recent congressional study of income inequality reported that from 1980 to 2008, the share of income earned by the wealthiest 1 percent of Americans doubled, from 10 percent to 21 percent.

Recent changes in the campaign finance landscape will fuel this trend, putting even more legislative muscle behind policies that help corporations and the wealthy, often at the expense of the middle class.

After the Supreme Court's radical decision in the Citizens United case, corporations now have the same rights to make political donations as individuals, drowning the voices of those who don't earn billions or employ lobbyists. And anyone who thinks campaign spending only influences elections is delusional; it's directly related to what laws are made or blocked.

At the same time, a bevy of organizations has sprung up to take advantage of Citizens United and existing tax laws by accepting donations to pay for political ads. Many of these donations can stay secret, and while they are thought to account for about 10 percent of election spending this year, their success in 2010 means they could grow exponentially in 2012.

Donor secrecy is insidious because campaign spending gives the clearest picture of who stands to win and lose in any given race.

To help solve these problems, the House of Representatives passed the Disclose Act, requiring companies and unions to report donations. But its prospects are dim in the Senate. As the New York Times reports, the current landscape is the result of a decades-long effort led by Sen. Mitch McConnell, the Republican leader, to eliminate restrictions on campaign financing. There's little chance McConnell's party, after making big gains Tuesday, will do anything to roll back its victories.

All of this might seem hopeless. Short of a constitutional amendment affirming that corporations are not the same as people, what can be done?

Plenty.

Corporate shareholders can demand that the companies they own either halt or disclose their campaign spending. Customers can do the same, using social networking tools to spread the word. It worked earlier this year, when Target said it would re-evaluate its practices in the wake of a consumer backlash over a donation to an anti-gay candidate.

And while corporations have more power over politics than ever, there is one important exception: They can't vote. That's one right still reserved for the people.