The overpopulated field of Christmas rom-com is long overdue for parody and it comes in tonight’s “A Clüsterfunke Christmas” (Comedy Central, 7 and 9 p.m.) from “Saturday Night Live” alums Rachel Dratch and Ana Gasteyer, who write, executive produce and star. It concerns a big city real estate exec set to buy a country inn who gets roadblocks from the spinster sister owners (Dratch and Gasteyer) but is attracted by their nephew (Cheyenne Jackson). 

It competes with a slew of original Christmas movies that don’t get the joke. Among them: “A Very Merry Bridesmaid” (Hallmark, 8 p.m.) with Emily Osment and Casey Deidrick, “Kirk Franklin’s A Gospel Christmas” (Lifetime, 8 p.m.) with Demetria McKinney, “The Jenkins Family Christmas” (BET, 8 p.m.) with Regina Taylor and Kim Coles, “Our Christmas Journey” (Hallmark Movies & Mysteries, 10 p.m.) with Holly Robinson Peete and Lyriq Bent, “Jingle Bell Princess” (GAC Family, 8 p.m.) with Merritt Patterson and Trevor Donovan, and “Christmas Beneath the Stars” (UPtv, 7 p.m.) with Maddy Foley. 

But how will any of them fare against the first seasonal showing of “It’s a Wonderful Life” (NBC, 8 p.m.)?

A documentary film “Silent Night — A Song for the World” (CW, 8 p.m.) looks into the history of the song and new versions by stars from Kelly Clarkson and Joss Stones to Randy Jackson and the Vienna Boys Choir. Hugh Bonneville narrates.

“Space Jam: A New Legacy” (HBO, 8 p.m.) makes its premium cable premiere. It’s followed by a new standup comedy specials, “Drew Michael: Red Blue Green” (HBO, 10 p.m.).