Rep. Jack Kemp (R-N.Y.) has won his first endorsement from a U.S. senator, and it comes from a state crucial to his presidential ambitions. New Hampshire Sen. Gordon J. Humphrey will endorse Kemp today in Concord and then tour the state with the him, Kemp spokesman John Buckley said.

Humphrey joins Rep. Robert C. Smith (R-N.H.), another of the state's leading conservatives, in choosing Kemp. "Now Kemp has the support of the two politicians in the state who actually have grass-roots organizations -- sending a signal that conservatives are endorsing Kemp and the moderates are elsewhere," Buckley said. He added that the just- announced New Hampshire steering committee of GOP rival Sen. Robert J. Dole (Kan.) "is chock full of moderates."

Kemp, who is banking on persuading New Hampshire conservatives that he is their only real choice, is expecting a boost from former Nevada senator Paul Laxalt's announcement last week that he will not enter the race.

Humphrey spokesman Bill Anthony said Laxalt's decision was the "catalyst" for the timing of Humphrey's endorsement: "He thinks it's time to get conservatives on board and stir up a viable candidacy for Kemp."

The most recent New Hampshire polls, taken in late spring, showed Vice President Bush having a wide lead, with Dole and Kemp competing for second place.