Michael Dukakis linked up with one-time Democratic presidential challenger Jesse Jackson on Saturday for a quarter-century tribute to Martin Luther King Jr. on the steamy hot steps of the Lincoln Memorial.

George Bush campaigned in Texas where his spokeswoman said he had already agreed to address a Marine veterans group in Dallas before being invited to participate in the Washington march.Without mentioning the Reagan administration by name, Dukakis said many of the late civil rights leader's dreams remain unfulfilled and promised to work to change that if elected president.

"We cannot look back or look down when we know that the cancer of racism and bigotry is still with us and that over the healed wounds of the past new wounds are opening in our cities and in our suburbs," he said.

"We have to look up, because that march for good jobs and real freedom didn't end that August afternoon 25 years ago. We have to march on."

Bush's decision to campaign in Texas emphasized his determination to go all out to win what his campaign chief termed the must-win state of all must-win states.

"I mean to run hard, I mean to fight hard and I mean to win Texas," Bush told a rally of party workers at Houston hotel.

The vice president praised his running mate, Sen. Dan Quayle of Indiana, and told the group he "is going to be a tremendous asset to this ticket and I am proud to have placed my bet on the future."

"We have a new generation," Bush said. "This man will measure up."

He then left for a couple of late afternoon stops with campaign chairman James Baker. It was Bush's first trip to Texas since he was chosen the Republican presidential nominee in New Orleans less than two weeks ago.

Baker told reporters the election is "a lot more winnable (for Bush) than a lot of sages were saying just two weeks ago."

"If there was ever a `must' state for a presidential election, Texas is it in 1988," Baker added.

As if to underscore that strategic assessment, the Democratic vice presidential nominee, Sen. Lloyd Bentsen, wrapped up a five-day campaign swing with an appearance at Austin, the capital of his home state, before flying back to Washington.

"George Bush comes to Texas, goes to Longview, and charges Mike Dukakis with being soft on the war on drugs," said Bentsen. "That is an outrageous misrepresentation."

Bentsen said the homicide rate in Massachusetts under Dukakis' governorship is half the national average, that Dukakis has added 1,500 law enforcement personnel, and has pushed programs to help victims of crime.

Meanwhile, Quayle was in California expressing confidence that his campaign is getting off the dime after being bogged down by questions about his National Guard service.

"I really feel a great deal of enthusiasm beginning to build," he said.