Blocking presidential primaries in some states is not unusual when an incumbent is running for reelection, officials said.
The Trump campaign pointed out that in 1992, when president George H.W. Bush was seeking reelection, Republicans canceled primaries in eight states; in 1996, when president Bill Clinton was running for a second term, Democrats canceled primaries in eight states, and in 2004, when president George W. Bush was up for reelection, Republicans canceled primaries in 10 states.
