The Tillis Campaign has been relatively cautious by not aggressively attacking his primary opponents. He'll need their supporters if he is ultimately the GOP candidate. However, there is another tidbit in these polls that shows winning over some of these folks may be an uphill climb no matter what.
Most of these polls also asked about head to head match ups against Kay Hagan. In all of them that did, there is a strong "anybody but Hagan" block - averaging around 40% to 45% of the general election population. However, among the leading GOP candidates, Thom Tillis is the one who more often trails Hagan in head to head match ups. (Hagan bests Tillis in 2 of the 3 polls) In the most recent PPP poll he is the only Republican from the entire GOP field trailing Hagan. All of these are within the margin of error, but that consistency in trailing Hagan may indicate that the Speaker is not carrying all of the "anybody but Hagan" block.
Add to that, comments like the recent one from NC Senator Bob Rucho (R-Meck) saying the establishment money will only follow Tillis in the general and not the other GOP hopefuls, and you might begin to think the establishment only cares about getting their guy elected. Sabotaging other GOP candidates in the general is an acceptable price to pay in the attempt to win the primary.
That's something to remember the next time you hear demands for party unity above all else.