MAKING NICE

Barack Obama and Hillary Rodham Clinton have unleashed advertisements in nearly all the 22 states that have Democratic presidential nominating contests Tuesday, a combined $19 million expenditure that is the most ambitious and geographically expansive television effort in a presidential primary.

On the Republican side, John McCain and Mitt Romney have a far more restrained advertising effort that started just this weekend and is focusing on a handful of states and national cable stations.

The advertisements are striking in that they are devoid of any overt attacks on opponents. (Though Romney has reprised an advertisement in which he attacks Clinton.) After weeks in which the race in both parties has featured flashes of intense personal animosity, the candidates all seem to have decided that they need to introduce and define themselves for a broad swath of the country in positive terms.

AH, YOUTH ...

Most can't remember a president that wasn't a Bush or a Clinton. And even Barack Obama, the youngest 2008 candidate at 46, is twice as old as today's teenage and early-20s voters.

Despite their advanced age, four candidates -- Obama, Hillary Rodham Clinton, Mike Huckabee and Ron Paul -- participated Saturday in "Closing Arguments: A Presidential Super Dialogue," a last chance to make their case to the energized youth voting bloc.

The event -- sponsored by the Associated Press, MTV and MySpace -- featured questions from moderators and from online and in-studio participants.

Each appearing separately, the Democrats pitched their college aid proposals; Huckabee, his theory of "vertical" leadership that breaks through the "horizontal" politics of left and right; and Paul, his belief that government is best when it gets out of people's way.

Clinton, noting Democrats are choosing between a female and an African American, said: "Whichever of us gets the nomination, we are making history." Equally mindful of history, Obama said the contest is not about the race or the sex of the candidates.

If it were just about his race, he said, "I wouldn't have to answer questions. I could just show up."

ALSO COMING TO MINNESOTA

• Hillary Clinton will hold a rally at 4-6 p.m. today in the Melby Gymnasium at Augsburg College in Minneapolis. Doors open at 2 p.m. For more information, go to www.HillaryClintonMN.com.

• Republican candidate Ron Paul will appear at 7 p.m. Monday at the U's Coffman Union, 300 Washington Av. SE., Minneapolis. The rally is open to the public.

WHAT COMES AFTER TUESDAY?

Well, yes, Wednesday -- and all the post-game breakdown of Tuesday's results. But the next round of primaries and caucuses is Saturday, when both parties square off in Washington and Louisiana, the Democrats face off in Nebraska and the Republicans in Kansas.

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