WASHINGTON — The 2010 Supreme Court decision that helped usher in a new era of political spending gave Republicans a measurable advantage on Election Day, according to a new study.
The advantage isn’t large, but it is statistically significant: The researchers found the ruling, in Citizens United v. FEC, was associated with a six-percentage-point increase in the likelihood that a Republican candidate would win a state legislative race.
And in six of the most affected states — Michigan, Minnesota, Montana, North Carolina, Ohio and Tennessee — the probability that a Republican would be elected to a state legislative seat increased by 10 percentage points or more.
In five other states — Colorado, Iowa, Texas, Wisconsin and Wyoming — Republican candidates were seven percentage points more likely to win.