Nick Corasaniti at NYT:
The four senators currently running for president — Bernie Sanders, Elizabeth Warren, Amy Klobuchar and Michael Bennet — have all had to detour from the campaign trail in the middle of a charged primary to sit for jury duty in the impeachment trial of President Trump.
With the race in Iowa incredibly fluid, the trial has become a scheduling speed bump for the senators. They risk losing hard-won advantages in a state that evaluates candidates on in-person appearances, while former Vice President Joseph R. Biden Jr. and Pete Buttigieg, the former mayor of South Bend, Ind., and others are able to press into face-to-face campaigning.
Though news media coverage has focused on surrogates working overtime for duty-bound candidates — Representative Alexandria Ocasio-Cortez appearing for Mr. Sanders in Iowa; Julián Castro stumping for Ms. Warren in Nevada; Abigail Bessler, Ms. Klobuchar’s daughter, hosting “hotdish house parties” in Iowa — the campaigns say they will use digital tools to keep the candidates directly connected with voters.