The only candidate who scored a near-win at Ames who really bombed at the Iowa caucuses was Phil Gramm. Gramm, as you noted, tied for first with Bob Dole in the straw poll, which reflected his success at fundraising and organization.
But Gramm participated in the Louisiana caucuses, which came before Iowa and thus angered many Iowans. Even worse, he lost those Bayou State caucuses to Pat Buchanan. Finally, he didn’t have PJB’s level of support among Iowa’s Christian conservatives. So Gramm did not get a ticket out of Iowa to the New Hampshire primary. Buchanan of course won the Granite State primary and would have won Iowa too if Alan Keyes had not been on the ballot.
George H.W. Bush won the straw poll and the caucuses during the 1980 cycle. Pat Roberston won the straw poll and came in second in the caucuses, beating out then Vice President Bush, in the ’88 cycle.