Jeff McCausland mocked Trump's offer to "teach him a few things" about running a military.
The former Red Sox pitcher has discussed running against the liberal senator.
“I don't think she understood the gravity of setting it up,” Biden said.
An email to House Republicans says it is "imperative" to stick behind the GOP nominee.
The Senate battle is in a virtual tie, a new poll finds.
A majority of both Republicans and Democrats see Russian influence.
"Trump is actually running behind Mitt Romney with union members," an official said.
"The keys still point to a Trump victory," Allan J. Lichtman said.
OPINION | Trump isn't perfect, but his message resonates deeply with Americans
"It's really not that hard to grasp," Clinton tweeted to Mark Kirk.