this money, the candidates must collect a specified number of signatures and small (usually $5) contributions. The candidates are not allowed to accept outside donations or to use their own personal money if they receive this public funding. Candidates receive matching funds, up to a limit, when they are outspent by privately funded candidates, attacked by independent expenditures, or their opponent benefits from independent expenditures. This is the primary difference between clean money public financing systems and the presidential campaign system, which many have called "broken" because it provides no extra funds when candidates are attacked by 527s or other independent expenditure groups. Supporters claim that Clean Elections matching funds are so effective at leveling the playing field in Arizona that during the first full year of its implementation, disproportionate funding between candidates was a factor in only 2% of the races. The U.S. Supreme Court's decision in Davis v. Federal Election Commission, however, cast considerable doubt on the constitutionality of these provisions, and in 2011 the Supreme Court held that key provisions of the Arizona law – most notably its matching fund provisions – were unconstitutional in Arizona Free Enterprise Club's Freedom Club PAC v. Bennett. This procedure has been in place in races for all statewide and legislative offices in Arizona and Maine since 2000. Connecticut passed a Clean Elections law in 2005, along with the cities of Portland, Oregon and Albuquerque, New Mexico, although Portland's was repealed by voter initiative in 2010. Sixty-nine percent of the voters in Albuquerque voted yes to Clean Elections. A 2006 poll showed that 85% of Arizonans familiar with their Clean Elections system thought it was important to Arizona voters. However, a clean elections initiative in California was defeated by a wide margin at the November 2006 election, with just 25.7% in favor, 74.3% opposed, and in 2008 Alaska voters rejected a clean elections proposal by a two to one margin. Many other states (such as New Jersey) have some form of limited financial assistance for candidates, but New Jersey's experiment with Clean Elections was ended in 2008, in part due to a sense that the program failed to accomplish its goals. Wisconsin and Minnesota have had partial public funding since the 1970s, but the systems have largely fallen into disuse. A clause in the Bipartisan Campaign Reform Act of 2002 ("McCain-Feingold") required the nonpartisan General Accounting Office to conduct a study