TV REVIEW : David Gergen, Ben Wattenberg Analyze the Political Parties : The two-part show examines the changes washing over the Democrats and Republicans since the ‘60s.

Democrat Bill Clinton is about to take his campaign for the White House to Texas, Mississippi and Arizona--states long held as Republican provinces. Democrats aren’t supposed to spend precious time in places like these, but it’s a symbol of the 1992 shift in the two major parties that Clinton, appealing to a broader constituency than any recent Democrat, is hunting in Bush country.

So commentators David Gergen and Ben Wattenberg may be accurate in their two-part analysis of the changes washing over both parties, “America’s Political Parties: Power and Principle.” (Part 1, on the Democrats, airs at 9 tonight on KCET-TV Channel 28 and KPBS-TV Channel 15; 8 p.m. on KVCR-TV Channel 24. The Republican segment airs next Friday at the same times.)

Their contention is that the liberalism of Lyndon Johnson’s Great Society programs and the conservatism of Ronald Reagan’s “trickle-down” capitalism gave the parties distinct ideologies that also ran them into the ground. A kind of center to center-right consensus, epitomized by Clinton, is now on the rise.

What is actually behind the report is a tale--though told from a distinctly neo-conservative view--as old as the Republic, of how American politicians, while having to win office from their left or right, must govern in the middle. It is this middle that causes gridlock and voter disgust, but also where the government was designed to be steered. Gergen and Wattenberg would have done well to provide some history to show that what happened to Democrats and Republicans from 1960 to 1992 is part of a continuum, not a startling shift.

Wattenberg’s account of the rise and fall and rise again of the Democrats is about an epic of vision destroyed by an avalanche of blunders. He accurately depicts John Kennedy as a centrist (social liberal, hard anti-Communist) whose domestic programs were pushed to the left by Johnson. But Johnson, pincered by Vietnam and the anti-war movement, as well as a white Southern backlash against civil rights, allowed his party to be split in two. As a result, the Democrats did not fully recover from the debacle of their 1968 convention until this year--with Jimmy Carter as a temporary blip in a long GOP hold on the White House.

While Wattenberg lambastes the “special interests” of peace, feminism, ecology and civil rights that he sees as sinking the Democrats, Gergen is silent on most of the “special interests” allied with the Republicans--small and large business owners, the military industry and major financial institutions. Only the religious right is exposed, yet Gergen perhaps underestimates the Pat Robertson wing’s growing hold on GOP political machinery.