He was a Republican counterweight to Republicans who might curtail wholesale abortion, so he was a maverick, and the press let him be. Kind of like John McCain, a tool.
As long as they needed him, he was their darling, and he was safe.
Then, in November 1992, as soon as the election was done, and an openly pro-abortion President had won the election, The Washington Post began running stories about Packwood and sexual harassment. (This pattern starting to look familiar, anyone?)
That's all true. But there was an amusing irony as a result. Packwood was seen by the Clintons as a potential Republican ally in passing health care. When the stories and his diary came out, he reverted to total party loyalty in an attempt to save himself. He led the charge in fillibustering a vote on Hillarycare, and there was no vote until the 1994 election when the Dems got massacred.
That is true, too...well, I suppose abortion was more important to them than healthcare, which is odd, but...given their liberal dogma...perhaps predictable!