A Michigan congressional candidate's last-minute switch from backing the Democratic nominee to endorsing his Republican opponent blew up badly on live TV, and it's a win for the candidate she abandoned.

• Haley Stevens dropped her endorsement of Democrat Abdul El-Sayed and backed Republican Mike Rogers, then went on CNN and couldn't give a straight answer for why.
• The switch came after she received over $30 million from pro-Israel donor groups, and it followed an ad tying US aid to Israel to affordability problems at home — the real motive appears to be pressure from that lobby, not anything she could say on camera.
• The flip-flop backfired: instead of hurting El-Sayed, his polling lead and betting-market odds both went up after the episode.
• Democrats broadly are seen as leading in several competitive races (Kansas, Ohio, Alaska, South Carolina, Texas, Michigan), suggesting a favorable night for the party overall.

Outlook: Watch election night results to see whether El-Sayed's bump holds and whether the backlash against pressure campaigns like this one continues to help Democratic candidates who don't cave.