WASHINGTON — * The US and the West are more likely to lend economic assistance to the Soviets now, according to Rep. Les Aspin (D) of Wisconsin, chairman of the House Armed Services Committee.One reason: the stronger, sounder program for reform of the Soviet economy that the West awaited is more likely to happen now. "You're going to see a rush of the reformers' agenda," said Mr. Aspin at a Monitor breakfast yesterday. "The reformers now realize there is no competition." The coup revealed that President Gorbachev - the man in the middle in Soviet politics - had no political base behind him. Instead, the country is polarized between reformers and the communist right by about 3 to 1, said Aspin. The coup failed, Aspin noted, because it happened too late to have strong hard-line institutional support and too early for the Soviet people to face economic desperation.