Across
1. They may be found behind paintings
6. Parts missing from the Venus de Milo
10. Often-misused pronoun
14. Make it on the podium
15. Some drag show props
16. State where the starred clues caucused
17. *Senator from Massachusetts
20. Longest river wholly in Switzerland
21. “Into the Unknown” singer in “Frozen II”
22. Examines a passage
23. Writer of limericks, say
25. Video game annoyance
27. *Senator from Minnesota
34. Ballpark figure
37. Chunk of marble
38. Tranquil
39. Gas in signs
41. Blouse or chemise
43. Dubious Himalayan sighting
44. Head over heels
47. A great deal
50. Study
51. *Representative from Hawaii
54. The Blue Jays, on a scoreboard
55. Sacred songs
59. Hello or goodbye, for 51-across
63. Motley ____
66. Without ice, as a drink
67. Each of the answers to the starred clues, as in the 2020 Democratic Primary
70. Drops out of the sky
71. Invalid
72. Amber, originally
73. Goes for
74. Nobel Peace Prize location
75. “Well, ____ you special!”

Down
1. Primitive weapon
2. Name on the Saudi flag
3. Oberon or Titania, in “A Midsummer Night’s Dream”
4. Itchy condition
5. Home of the kraken
6. Biblical brother
7. Doesn’t keep
8. Thank you, for 51-across
9. Philadelphia to Dover dir.
10. What a police informant may wear
11. Bar mitzvah dance
12. Was in the red
13. Operates, as a station
18. Mineral in many green gemstones
19. Debate
24. Leading characters in “Mamma Mia?”
26. “Six-pack” muscles
28. “2 Broke Girls” actress Dennings
29. Word sometimes “dropped” prematurely in a relationship, colloquially
30. Have a bawl
31. Pay attention to
32. Pot grower?
33. Bridle strap
34. Meter or liter
35. Waiter’s handout
36. Favorability metric for the starred clues
40. Rejections
42. Trivia night site
45. Life-or-death
46. Massage target?
48. Attired like a superhero or vampire
49. Storefront listing, for short
52. One of the inverse trigonometric functions
53. Allergy causing skin-flecks from pets
56. Renter’s contract
57. Morning, in Marseille
58. Insert for a blocked blood vessel
59. Picked locks?
60. Spring
61. Overlook
62. Composer Zimmer
64. Symbol of thinness, in a common simile
65. Press Control Z
68. Recently ousted Bolivian president Morales
69. 401(k) alternative