Poll watching and election coverage (5 p.m., CNN, Fox News, MSNBC, BBC America, 5:30 p.m., ABC, CBS, NBC, 6 p.m., TV One, 7 p.m., Fox, 9 p.m., PBS) should dominate prime time and beyond.

Beyond the candidates, what TV networks and personalities will emerge as winners and losers tonight? MSNBC has virtually turned over its prime-time schedule to advocate for Barack Obama. But their ratings might suffer if he wins. Having thrived in opposition, Keith Olbermann and Rachel Maddow may seem dull supporting a sitting president.

Conversely, Fox News, and particularly Sean Hannity’s program, has been the place to turn to for anti-Obama news, rumor and innuendo. Again, their ratings would probably not be enhanced by a McCain victory. Like talk radio, Fox News exploded during the Clinton years, so you have to figure its management would be more than comfortable as the voice of the opposition.

So no matter who emerges as our next president, one of the cable-news outlets could win by losing. Or lose by winning.

And just what is the net electoral effect of so much political chatter on cable news and talk radio? Is it politically effective or so much noise aimed at captive constituencies? To see how this process might actually boomerang, viewers should follow one particular House race tonight.

Telegenic Minnesota Rep. Michele Bachman has been a fixture on cable news, appearing frequently on “Larry King Live” and “Hardball with Chris Matthews,” among other shows, advancing her conservative Republican positions.

A few weeks back, she suggested the need to investigate anti-Americans and un-Americans in our midst. Bachman’s comments were hardly unusual on a medium that encourages the outrageous. It sounded like something Hannity says on any given night. But her charges galvanized her opponent’s fundraising efforts, and the controversy caused the Republican national campaign to suspend financial support for her race.

In short, Bachman’s cable celebrity may have hurt her efforts. If she loses, she may have literally talked herself out of a safe seat in the House. We should know sometime after Minnesota polls close at 8 p.m. Of course, should she be defeated, Bachman may be looking for a job on cable television.

¢ Viewers looking for an escape from politics can turn to a marathon of movies featuring the Italian Stallion “Rocky” (4:30 p.m., AMC), “Rocky II” (7 p.m.,) and “Rocky III” (9:30 p.m.).

Tonight’s other highlights

¢ “Nova” (7 p.m., PBS, check local listings) repeats a look at the jet dogfights of the Korean War and the search for evidence of a downed American pilot.

¢ Escape politics with three consecutive episodes of “Paris Hilton’s My New BFF” (7 p.m., MTV).

¢ Three hours of adventure, heroism and survival unfold on “Most Amazing Moments” (7 p.m., National Geographic).

¢ “Half Ton Man” (7 p.m., TLC) profiles a bed-ridden Nebraska man who weighs 1,072 pounds.

¢ Mike Rowe discusses past presidents who held dirty jobs on “Dirty Jobs” (8 p.m., Discovery).

¢ Vick offers a bounty to gang members on “The Shield” (9 p.m., FX).

¢ Jon Stewart and Steven Colbert co-host “Indecision ’08: America’s Choice” (9 p.m., Comedy Central) a live election comedy special.