Former White House chief of staff William Daley abruptly dropped out of the race for Illinois governor on Monday. Daley says that he wasn’t sure if he wanted to devote time to a long, hard campaign followed by four years of office. Spokesman Peter Giangreco confirmed that Daley was ending his bid. The announcement came less than four months after Daley said he would challenge Gov. Pat Quinn for the Democratic nomination next year. Daley had criticized Quinn for his handling of the state’s pension crisis and other issues. Daley would have been just the latest son of the Richard J. Daley, the mayor of Chicago, to run for office, joining his brothers, Richard and John.

This story is significant because it lets viewers know that a candidate has dropped out of the race as governor.
The impact is that supporters of Daley will now have to support a different candidate.

is that ok for why the story is significant, and what is the impact of the story?

Sounds right, yes.