Spending in a seven-way race for seats on the Pennsylvania Supreme Court has eclipsed $15.8 million, making it the most expensive judicial election in U.S. history, according to advocacy groups. 

Three Republicans, as many Democrats and one Independent candidate are vying for three seats on the state's high court. The three candidates who collect the most votes will win the seats. The previous national record of $15.19 million was set in the 2004 Illinois Supreme Court race between Lloyd Karmeier and Gordon Maag, according to an analysis of state disclosures by Justice at Stake and the Brennan Center for Justice, two groups that support limits on money in judicial elections. 

The figures in the Pennsylvania race are likely to rise, as more records are filed, according to the groups. 

Spending on judicial races has been building since the 1990s, when trial lawyers and business groups began trying to influence elections. Outside groups with broader political goals then joined in. The trend has accelerated since the Supreme Court struck down federal limits on corporate and union political spending in its 2010 Citizens United ruling. 

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