One thought that is easy to lose sight of in the waves of campaign and media-stirred controversy over Candidate Barbie's clothes, Barack Obama's past associations and whether government-directed aid to persons afflicted by the current economic woes is socialism is that, in the end, Americans will be voting Tuesday to express their choice between one candidate and the other.

In a way it is necessary to consider one's personal reaction to the peculiarities of the candidates, but, in the end, the important question is, under which candidate will America do best over the next four years?

My answer is Barack Obama.

Readers of my column over the seven years that I have been in Pittsburgh may not be surprised, considering the degree to which I have taken the wood to the administration of President Bush. But it is not only my natural tendency, but also part of my job as I see it, to point out policies or actions that I think are mistakes on the part of whatever administration is in power.

Whichever of the two candidates wins, I promise that I will quickly begin picking at what I think his administration is doing wrong, as well as occasionally focusing on what it is doing right.

Both of Mr. Obama's campaigns, basically against Sen. Hillary Clinton in the primaries and against Sen. John McCain in the actual presidentials, turned out to present relatively easy choices for me. I did not want to see the Clintons back in the White House, whichever one of them had the presidency. I lived through the 1990s and consider them to have been a better period for the country than the Bush II presidency, although I am also able to wax eloquent on what was wrong with the Clinton presidency.

During the primaries and now, I have considered Mr. Obama to be the political leader, among all the Republican and Democratic contenders, to offer American leadership for the brightest future possible. When I supported him in the primaries I didn't know -- none of us yet knew -- just what a perilous minefield that Bush administration deregulation and other financial mismanagement had dropped us into.

The Republicans then made the final choice easy for me. I am not sure what possessed them to nominate Mr. McCain. Part of it was his flawed competition. Who will ever forget former Sen. Fred Thompson and former Gov. Mike Huckabee? In some respects it reminded me of the candidacy of Sen. Bob Dole in 1996 against the then-popular President Bill Clinton. Mr. Dole wanted the nomination, in a sense it was his turn, and he basically agreed to take the fall that was coming to any Republican candidate that year, for the glory of it. (Think of what it did for his speaking and advertisement fees.)

Mr. McCain is old. Take a look at before-and-after television clips of Mr. Bush to see what the presidency does even to a relatively carefree occupant of the White House. Mr. McCain has had cancer and no one can gauge what effect his years under the tender care of Vietnamese captors may have had on his health.

The first responsibility of a presidential candidate is to choose a competent vice presidential candidate to take his place if and when. The Republicans' back-up quarterback doesn't know the playbook and can't throw a long pass. Furthermore, after eight years in power the Republicans' reserve bench is, in effect, empty. A McCain administration would be staffed by Bush leftovers and holdovers, those who brought us to where we are now.

Mr. Obama, by contrast, has not only a lot of forward-looking ideas for the economy and America's relations with its allies and opponents, he also offers a new approach, some new people and the hope and vigor of relative youth. What appealed to voters in the Democratic primaries is what appeals to them now -- the alertness, the brightness of his mind and speech, and the spring in his step.

There is also an argument -- that I find particularly appealing as a progressive, former Rockefeller Republican, back when there was such a thing in the Republican Party -- that says that the best thing that could happen to America at this point is for the Republicans to get soundly trounced. I believe strongly in the importance to good governance in America of a strong two-party system.

The Republican Party is now monolithic, almost entirely controlled by its right wing. This phenomenon was illustrated clearly in the choice of Alaska Gov. Sarah Palin as vice president. Mr. McCain wanted Sen. Joe Lieberman of Connecticut or former Gov. Tom Ridge of Pennsylvania. Those who control the party rejected them because they are pro-choice and proposed former Gov. Mitt Romney of Massachusetts. Mr. McCain rejected Mr. Romney on grounds of personal incompatibility and made the arbitrary, undeliberated choice of Ms. Palin as his running mate.

Now, a badly beaten Republican Party would be forced to regroup toward the center.

Voters have a choice Tuesday between Mr. McCain and Mr. Obama. It is not necessary to love either of them to vote for one of them. In my view, Mr. Obama needs to win and the Republican Party needs to lose for America to have its best prospects for future political and economic health. I urge you to vote for Mr. Obama.