Former Delaware governor Pierre S. (Pete) du Pont IV today became the first 1988 presidential candidate in the eyes of the law and said he starts his campaign from a "wonderful position. I'm unknown, I'm underrated and there's nowhere to go but up."

Du Pont, 51, a Republican, announced to supporters here that he had notified the Federal Election Commission that he has formed a committee to raise money for a 1988 campaign. That notification makes him a presidential candidate under FEC rulings.

Du Pont indicated that he planned to formally announce his candidacy in September. "Assuming we can assemble the necessary resources this summer, in the fall I will become a candidate for the presidency of the United States," he said.

He noted that his committee "is neither an exploratory committee such as that filed by former senator Howard Baker nor is it a multicandidate PAC such as that filed by Vice President Bush. Rather, 'Pete du Pont for President' is the first formal presidential campaign committee filed by a major candidate in this cycle."

He added, "The way to do something is to do it. If you're interested, don't bother with exploratory committees and things like that."

Du Pont announced the committee's formation at Wilmington's Grand Opera House at a breakfast attended by about 1,000 supporters, many of whom worked for him in previous campaigns or while he was governor.

"It's time to start, time to raise money, time to get a staff together, time for me to get ready to go to New Hampshire and Iowa and talk about the direction the country should take," du Pont said.

He said that his goal is to raise $1 million before next March and $8 million to $10 million to campaign in Iowa and New Hampshire. His priorities are to raise his name identification and to campaign in the early presidential-delegate selection states in the hope of making a showing that would give him impetus in later primaries.

Recent polls indicate that only about 20 percent of the respondents recognize his name and that he is the presidential choice of only about 1 percent of Republicans.

Du Pont said that he did not think any other likely Republican presidential candidate was a clear front-runner.

He also contended that his two terms as governor from 1977 to 1985 give him executive leadership experience that the others lack. A moderate on social issues and an advocate of supply-side economics, du Pont ran state government in a period when Delaware went from near bankruptcy to one of the most prosperous states.

He also served two terms in the U.S. House of Representatives and one term in the state legislature.

He praised President Reagan as the "captain of the ship of state" who "assumed command when it was in terrible trouble, listing to the left and nearly out of fuel, and who has been able to steer a course that will allow it to complete its voyage" and enable America to prosper.

"Some of the other candidates think they're qualified because they have been on the crew. One is the first mate," he said in reference to Bush.

"Some are navigators with special ideas on the direction it should take," he continued, referring to Rep. Jack Kemp (R-N.Y.), another likely candidate and an architect of supply-side economics. "But they have never run the ship."