#2 JBL - Yes
Excluding a slightly misleading 18 runs as Hardcore Champion -- at a time when the title was defended under 24*7 rules leading to multiple championship reigns lasting mere minutes -- JBL has won just seven titles during his 20-year career in the WWE.
However, in addition to his three reigns as WWE tag team champion as part of the APA, JBL has won the WWE, Intercontinental and the United States title once each which qualifies him for the Grandslam.
His first singles title victory came in 2001 when he beat The Hurricane for the European Championship on RAW.
Uniquely, JBL has either won or lost all his primary singles titles at a Wrestlemania.
JBL held the WWE title for nearly a year in 2004 before losing it to John Cena at Wrestlemania 21. The next Wrestlemania, he beat Chris Benoit to win the US title.
At Wrestlemania 25, he lost his Intercontinental title to Rey Mysterio in a record 21 seconds which turned out to be his final WWE match.