Even if U.S. Senate Republicans approve the next U.S. Supreme Court justice before the election, Democrats could add more justices if they sweep the election.
Robert McWhirter is a constitutional expert in Phoenix.
"In fact, the number of justices for a long time was five. At one point, as I recall, and I would have to look this up, I think there were as many as 12 justices," McWhirter said. "But then nine came in toward the end of the 1800s, and it's pretty much stabilized there.
McWhirter said Arizona Gov. Doug Ducey recently increased the number of Arizona Supreme Court justices. McWhirter says Ducey has appointed almost all of the justices.
EDITOR'S NOTE: The smallest number of Supreme Court justices was six from 1789 to 1807 and the largest number was 10 from 1863 to 1866.