I have some experience with Nevada politics, and have no affiliation with any of the aforementioned candidates, so here is my candid assessment:
Congressman Dean Heller was the ideal candidate, but he already has (prematurely in my view) announced he is not running and is staying in his safe House seat - apparently no fire in the belly.
Brian Sandoval would be the next best candidate - but it looks for sure that he resigned his Federal Judicial position to run for Governor instead.
Sue Lowden is the most electable of the other names mentioned. She is telegenic, has won a state senate seat previously, an has access to BIG bucks through her husband Paul, who used to own the Sahara Hotel. All of those are big pluses. The downside is that she has been out of politics for a long time, her “grass roots” abilities are suspect, and her views might be a bit on the moderate side.
Danny Tarkanian has the famous name, and currently leads in polls. However, he is a less-than-compelling public speaker and has lost in two previous attempts at local and state offices - not an inspiring track record. The famous name obviously helps, but he will need to show more skill and savvy to beat a candidate who can be ruthless and will be spending upwards of $25 Million Dollars.
Sharon Angle is the most conservative of the candidates mentioned, and she is also a strong campaigner. She has, however, lost GOP primary races for State Senate and Congress, is from up North, and has little money or statewide name recognition.
Bottom line: At this point, I think that Sue Lowden is probably the strongest of the potential GOP candidates, and based on his defensive comments about her I think she is the candidate Sen. Reid fears the most as well...
Jim Gibbons is badly damaged and likely to lose to any Dem nominee, which is why Judge Sandoval is running for Governor. Hopefully Gibbons will do the right thing and stand aside for the good of the party.