If you’re sick of sound bites but don’t have the time to watch political life unfold in real time on cable’s C-SPAN, the channel has an enlightening way to follow the presidential campaign. Road to the White House is a weekly digest that shows big chunks of the candidates’ stump speeches, their TV ads airing in primary states, and footage from some of their more freewheeling encounters. On one show last month, for instance, Road ran most of Sioux Falls, S.D.’s ”Candidates’ Forum,” a debate that included the six Democratic hopefuls. That’s right, six — Clinton, Tsongas, Brown, the then-still-running Kerrey and Harkin, and former Irvine, Calif., mayor Larry Agran, the invisible Democrat in this election, despite the fact that, as he pointed out, ”I’m on dozens of ballots all across this country.” So progressive he makes Jerry Brown look like Fred Flintstone, Agran is a real pistol, and it was an informative gas to see him added to the debate mix. Road to the White House will continue offering the stuff the Big Three networks can’t be bothered to show us right up to November. Be a patriot and tune in.