Forget the scenarios of a stalemated Democratic convention or unelected delegates overriding elected ones, at least for now.

Barack Obama appears well on his way toward winning his party's presidential nomination. Hillary Clinton's campaign is in deep trouble.

The evidence goes beyond the Illinois senator's increasing successes in caucuses and primaries, climaxed by Tuesday's sweep in the "Potomac Primary" that vaulted him ahead of Clinton in elected delegates and the popular vote.

More important, since they fought to a Super Tuesday draw, almost every Clinton move has suggested a campaign in trouble. This includes a shakeup in her top command, increasing evidence of money woes, her challenges for more televised debates and statements dismissing the significance of races she lost in caucus states or those with large African-American populations.

It's hardly a positive sign that she is putting her principal stress on a primary three weeks away in Texas, rather than this week's tests in Hawai'i and in Wisconsin, a mostly white state that historically has played a crucial role in Democratic contests.

That said, this race is not over. The unexpected can always happen.

Obama needs to win in Wisconsin and make strong showings March 4 in Texas and Ohio. Clinton's hopes may depend almost totally on getting enough support from Hispanics in Texas and blue-collar Democrats in Ohio to stem the Obama wave.

But Obama's increasing delegate totals suggest that Clinton not only has to win Texas and Ohio but do so decisively. If she does — and follows up with a victory April 22 in Pennsylvania — she would slow the Obama momentum, and the dreaded convention deadlock could become a reality.

A lot would depend on the 800 party and elected officials who have automatic delegate slots and on the ultimate decision on what to do about the banned delegations from Florida and Michigan.

That could be a mess, with in-fighting to win the superdelegates and credentials fights over whom to seat from the two states whose primaries the Democratic National Committee ruled illegal because they were held too early.

At the moment, however, that scenario seems less likely.

If Obama continues to do well, superdelegates — mostly highly pragmatic politicians — will want to embrace, rather than resist, him.

If he enters the convention with a majority of elected delegates, he will have a major say on what happens to the Florida and Michigan delegations.

And his support continues to grow among key voter groups, as shown by his stunning showing in Virginia, a so-called "purple" state that is evolving from Republican to Democratic and will be hotly contested in November.

His support among white voters — 24 percent last month in South Carolina and more recently in the upper 30s and low 40s — reached 52 percent in Virginia, according to network exit polls. He attracted majorities of voters with less education and lower incomes, the heart of Clinton's base. His support from blacks hit 90 percent.

He may need to approach those levels to win states like Wisconsin, where the 2004 Democratic electorate was 89 percent white, and in Ohio, where it was 81 percent. In Texas, he'll need to improve his showing among Hispanics, who may cast more than a fourth of the primary vote.

It was to shore up that base that Clinton headed for heavily Hispanic South and West Texas this week while Obama was in Wisconsin. She may benefit from the fact that the two candidates will debate next Thursday in Austin, two days after what both campaigns believe will be an Obama victory in Wisconsin, though a recent poll showed her a few points ahead.

But Clinton not only has been losing recent primaries but losing them by large margins. She has reached 40 percent just once since Super Tuesday, in Maine.

A Wisconsin loss could be especially devastating, given demographics that should favor her and the state's historic role in Democratic primaries. John F. Kennedy won his first big primary there in 1960 against neighbor-state rival Hubert Humphrey; George McGovern made his crucial breakthrough there in 1972; Jimmy Carter won a key test in 1976.

All but two Democratic nominees since 1960 have won Wisconsin's primary.

If Obama can match that, he'll pad his lead and put even greater pressure on Clinton to win in Texas and Ohio, lest his momentum prove irresistible in the remaining Democratic contests.

Carl P. Leubsdorf is Washington bureau chief of the Dallas Morning News.