No, you’ve given false information.
It was Rep. Steve King of Iowa:
http://www.freerepublic.com/focus/f-news/3431441/posts
Here’s what King says about Trump in the video from the link I gave you:
“he needs to reassure us on his appointments to the Supreme Court” meanwhile Trump had already issued a list which included Gorsuch and others similarly approved by strict conservative standards.
Rep Steve King of Iowa then goes on to say “It would be good for him to sit down with some people in Congress, house and senate, and ask us for our input, and then receive that input. John McCain did that eight years ago to great effect.”
Steve King supported Ted Cruz during the primaries, so yes, he did initially oppose Trump. However, once Trump became the nominee, King supported Trump’s candidacy 100%. The problem with “never Trumpers” isn’t that they supported someone else during the primary, but that they continued to oppose Trump (and implicitly or explicitly support Hillary) in the general election. Steve King (unlike the unrelated Peter King) was never one of these.
The title of that is...
Rep.(Steve) King: Trump needs to reach out to the conservatives (video)
Which hardly equates to "trying to kill his nomination."
Here is the truth of the matter which you can't handle...
Steve King affirms support for Trump at top of Republican ticket Oct 11, 2016
Long Island Rep. Peter King among Republicans horrified by Donald Trump Mar 01, 2016