Former Vice President Joe Biden continues to lead President Donald Trump in Arizona with support reaching the critical 50% level with less than a week before ballots are sent out, a new poll finds.
The same statewide poll found Democrat Mark Kelly with a commanding lead over Sen. Martha McSally, R-Ariz., suggesting Democrats in the state could sweep the top two races for the first time since 1944.
David Paleologos, director of the Suffolk University Political Research Center in Boston, said Cindy McCain's endorsement of Biden happened just as the poll began and could be significant.
"Her endorsement really is important demographically in ways that a lot of people aren't picking up," he said, noting that her backing likely has the most impact on whites and moderates.
And Biden reached the 50% mark late in the race and with only 2% of respondents undecided, he said.
"That's an important threshold to hit," Paleologos said.