It would have been highly unorthodox, but I always thought that Gore was hobbled by the allergy to bluntness and disruptive and disarming candor and his sense of obligation to meet an expected politician's 'script' when dealing with the personal ethical bagged Bill Clinton left on his lap.
Clinton left office with a high approval rating, based on the state of the economy, overall peace and prosperity. He was tarnished by his own actions, which his opponents kept in the public view, but they made themselves look somewhat bad in the process too. Still, it was enough that Gore had a dilemma of trying to distance himself and shake a stigma of association while still getting credit for achievements of the administration. Instead, people outraged at Clinton or partisan already could take out their anger by supporting his opponent, and he didn't have the rogue-ish charm and folksiness to win them back. He didn't use Clinton as much as might have been ideal for strategy or campaigning. But Bill's personal baggage was a reasonable reason not to.
I've long thought Gore should have bluntly addressed this issue of distancing, with a bold approach. Deploy Clinton personally to campaign for him and try to boost turnout only among niche audiences he was especially popular with at the time. Take his political advice behind the scenes early and often. Even in front of other audiences where he is not brought along, sometimes use his types of words and phrasing. But address openly among white, moderate, swing audiences Bill's personal issues. Not at any length. But in brief answers in questions, 'yes, the President has some personal issues to work out'. 'I see this administration as a having many successes on many policy issues, but I don't see this White House as a model for conducting my household, or personnel policy in my workplace, or communication with my colleagues in other branches on either side of the aisle.
This can be summarized in two shorter sayings or slogans. The short, bumper sticker is simply this: "Gore for President: It's like Clinton, Rated PG"
The longer version would be "Gore for President: No interns, no property deals, just the great economy and governance you've come to know and love"