THE PRESIDENTIAL SHOW did not close in Philadelphia. In fact, the Pennsylvania presidential primary, which four years ago effectively secured the Democratic nomination for Jimmy Carter, provided emergency (if temporary) resuscitation to the candidacies of George Bush and Edward Kennedy.

For the president and Sen. Kennedy, the scene of the action now switches to Michigan and that state's 141 convention delegates, who will be chosen on Saturday. Michigan has one of the more unorthodox delegate-selection procedures currently operating in the era of reform. All or part of the 41,717 enrolled state party members will participate in 89 separate caucuses throughout the state. Sen. Kennedy, having long ago forsaken his original theme of "leadership," is now arguing an "industrial state" strategy. This approach of the challenger (which conveniently over-looks his defeat in Illinois) obviously must include a win in economically distressed Michigan, in order to survive as a viable strategy.

Michigan also holds some encouragement for Mr. Bush, who, during the recent stampede by ranking Republicans of all types to ronald Reagan's bandwagon, was endorsed by that state's popular Republican governor, William Milliken. Michigan Republicans, ignoring the bizarre example of their intra-state opposition, will hold a primary on May 20.

Before the Michigan balloting, Mr. Bush will face Mr. Reagan on May 3 in Texas. In 1976, Mr. Reagan swept the Texas primary against former president Ford and, this time he has the all-out support of former rival John Connally. George Bush is registered to vote in and receives his mail in Houston, which means that Texas is Mr. Bush's home state. Candidates are, for reasons that are not totally clear, invariably expected to run better in their home states than elsewhere. Already this year, Mr. Bush has won in Massachusetts (the state of his birth), Connecticut (the state of his youth) and Maine (the state where he vacations). Three home states are quite enough for any candidate to contend with. George Bush is entitled to underdog status in Texas.

The real "winner" in the Pennsylvania results may very well be Rep. John B. Anderson, who is expected to announce as an independent candidate for president today. The central premise of the Anderson candidacy is a November general election between Jimmy Carter and Ronald Reagan.Tuesday's results probably did not seriously diminish the likelihood of either man's being his party's eventual nominee. But both Mr. Carter and Mr. Reagan are still very much in fights with increasingly aggressive opponents, neither of whom apparently has any intention of going quietly or without saying everything that is on his mind. And Mr. Anderson needs, most of all, time out of the spotlight to qualify for listing on as many state ballots as possible. Pennsylvania may have given him that time.