HARTFORD — Matt Lesser could never have raised the money to compete in a legislative election in most states. He was a 25-year-old local planning commissioner facing a former secret service agent for Richard M. Nixon who had been a fixture in local politics for two decades.

Yet he won an improbable victory in 2008, partly as a result of his home state’s solution to what some observers call the gravest threat facing American democracy: the ever-rising influx of millions of dollars in campaign funds.

At a time when a handful of anonymous super-rich individuals can secretly finance political committees, and when more money than ever saturates campaigns, Connecticut helped fund Lesser’s campaign with an innovative public financing system.

“I tried to get other people in my area to run,” said Lesser. “I found out about the public financing program and realized if nobody else wants to do it, I could.”

So far, however, Connecticut stands out as an exception in a nation awash in private campaign dollars.

Around the country, elections are stacked in favor of incumbents and insiders who have access to increasingly large pools of campaign money from a slew of outside groups willing to tilt the scales even more in their favor.

The amount of money spent on federal elections in years when the presidency is at stake has more than doubled in the last 12 years, from $3.1 billion in 2000 to $6.3 billion last year, according to the nonpartisan Center for Responsive Politics.

One reason for the spending spike is a series of Supreme Court rulings, including the 2010 Citizens United case that opened the door for more corporate and labor union money, as well as a separate Supreme Court decision that allowed some contributions to independent groups to remain secret.

As a result, campaign finance watchdogs expect the 2014 election to see even more concerted efforts by secretly funded outside groups to influence the outcome.

In the last election, for example, Americans for Prosperity, a nonprofit political committee founded by oil tycoons David and Charles Koch, spent $122 million in the 2012 elections, an amount that wasn’t revealed until recently. The funders behind some other groups remain secret.

“The anonymous money I think is just ridiculous,” said US Senator Angus King, an independent from Maine. “Nobody’s allowed to go to a Maine town meeting with a bag over their head. If you want to influence public policy, tell us who you are.”

Critics said the massive influx of money has intensified congressional dysfunction. Many lawmakers spend hours per week on the phone begging for money; some even dash from casting a vote on the floor of their chamber to dialing for dollars at phone banks in a building near the Capitol.

Even some of the most powerful and entrenched members of Congress feel they are under constant threat. The Senate Conservatives Fund, one of several outside groups that helps insurgents defeat mainstream Republican candidates, ran a television ad criticizing the minority leader, Mitch McConnell, in October after he brokered a compromise that ended a 16-day government shutdown.

Congress has in the past tried to restrict campaign spending only to see reforms wither away.

In the post-Watergate era of reform, lawmakers in 1974 instituted strict contributions limits. Some limits still exist such as those on direct donations to candidates. But there are no limits on individual contributions to independent committees that work in favor of causes and candidates, as a result of the Supreme Court’s Citizens United decision that equated money to freedom of speech.

Meanwhile, the effort to create public financing of presidential campaigns has all but failed. The post-Watergate measure that enabled people to check a box on their tax returns to give a few dollars to help publicly finance presidential contests has become, in recent years, gradually irrelevant.

Neither President Obama nor Republican nominee Mitt Romney took advantage of public financing for the 2012 primaries because they didn’t want to abide by accompanying spending caps.

Meanwhile, Connecticut has demonstrated how beneficial such a system can be, at least on a local level.Lawmakers in Hartford radically altered their campaign finance laws in 2005 after the jailing of a governor on corruption charges spurred a slew of bipartisan good-government measures.

Lesser, under the public financing provision, had to raise $5,000 in small contributions from people who live in his district, and then he received $25,000 more from the state for his election campaign. The amounts candidates raise and spend increase with the level of the office. State Senate candidates must raise $15,000 to receive about $90,000 more, whereas a candidate for governor is eligible to spend a combined $7.5 million in the primary and general elections.

Candidates who agree to the system can neither take money from state contractors and political action committees nor accept contributions of more than $100 per person.

The matching money for the program comes from the state’s unclaimed property fund, allowing lawmakers to make the case that they are not using direct tax dollars, though they are still spending public money.

Nearly four of five candidates now participate in the program. In the most recent gubernatorial election, a publicly financed candidate, Dannel P. Malloy, defeated self-funded candidates who far outspent him in both the primary and general election.

“You’re not endlessly chasing dollars throughout the campaign season,” said Malloy, a Democrat. “And I think it gives some level of confidence to the citizenry that there’s a system in place that tries to lift the influence of money to the greatest extent it can, in a post Citizens United environment.”

The number of uncontested seats in the Legislature has been in steady decline since the law took effect in 2008. Last year, only 32 of 187 seats went uncontested, fewer than in any year since the secretary of state began tracking the numbers in 1998.

Proponents of the law believe the impact of the reform was demonstrated in a victory over special interests in 2009, just after the first batch of publicly financed candidates took office. For decades, beer and soda distributors had kept unclaimed nickels from the state’s bottle deposit law. The money added up to between $20 million and $30 million a year.

But every time lawmakers threatened to reclaim those nickels on behalf of taxpayers, the distributors and their lobbyists — major campaign contributors — ascended to the state Capitol to kill the measure in committee.

Almost immediately after the 2009 session began, the first one after publicly financed elections, the bill passed easily on a bipartisan vote.

“It was just a simple good policy tool that had been bottled up by political influence,” Lesser said, asserting that the state’s campaign finance system helped make passage of the bill possible. Could such a publicly funded campaign system be implemented on the federal level, perhaps ameliorating the congressional gridlock?

Congress would have to agree to pay for it, and it could easily cost billions of dollars. Such bills have been offered up repeatedly over the years, and consistently been brushed aside. Vested interests are gored when the power of money in politics is reduced. A sense of crisis, and unity in outrage, such as existed after Watergate may be required.

The other piece that advocates say is essential to cleaning up the system — limits on outside spending — might be even tougher, requiring a change in the Supreme Court’s make-up or a constitutional amendment.

“If everybody had to receive public money instead of special interest money,” said Robert Stern, former president of the Center for Governmental Studies in California, “government would be a lot different.”