Those 5 or 6 Democrat senators from red states running for reelection will have to weigh the consequences carefully before they oppose the nominee. My guess is that they will choose wisely and vote for confirmation.
If their vote will be the deciding vote on anything, they'll side with the Dem leadership every time. If something will pass anyway WITHOUT their support, the Dem leadership will probably allow them to side with the Republicans, in order to increase their chances in the upcoming election. It's their way of fooling the voters into thinking they aren't under the thumb of the leadership.