In mid-April 2015, there were 14 GOP contenders. The top 3 in the polls were Gov Scott Walker, Gov Jeb Bush, and Sen Marco Rubio. Sen Rand Paul was consistently in the top 5. Mr Trump hadn't announced yet....
APR 16-21 2015 Quinnipiac: Rubio 15, Jeb 13, Walker 11, Cruz 9, Paul 8, Christie 7, Huckabee 7
APR 18-20 2015 YouGov: Walker 15, Jeb 13, Cruz 11, Paul 11, Carson 10, Rubio 9, Christie 6, Huckabee 5
APR 16-20 2015 Ipsos Online: Cruz 18, Walker 14, Jeb 13, Carson 9, Rubio 9, Paul 9, Christie 7, Huckabee 7, Santorum 6
APR 16-19 2015 ORC: Jeb 17, Walker 12, Paul 11, Rubio 11, Huckabee 9, Cruz 7
Walker dropped out in OCT 2015. Jeb raised and spent $150m to get 3% in the opening Iowa Primary. Rubio stuck around the longest of the early contenders and still only finished 4th. Rand dropped after the second Primary, in NH, where he failed to top 1%.
In short, this is a long, long way from being decided.
(Future Pres Trump declared his candidacy on JUN 16, 2015. Gov Kasich was the last to join the party on JUL 21, 2015, and the last to leave, a day after Cruz conceded in JUL 2016.)
I can’t remember but were there rumblings of Trump getting in in April 2015? Honestly, I don’t remember anyone talking about him getting into the race until he actually did, perhaps a week before. Once he got into the race, I clearly remember he shot to the top. During the first debate I think it was Walker in first and Trump in second.
Looking at it from that perspective, I don’t see any of the candidates out there that are thinking about it able to jump in and zoom to the top. It’s hard to speculate on some unknown jumping in. I agree with you that we are a long way from sorting this out and the Dems will possibly coalese around one of these candidates. However, I just don’t see it.
The reason is that Bernie has a huge war chest and a devoted following of 25 percent. Then there are the other Dems that are deathly afraid of him winning the nomination. I think that may be close to that 75% left. People may say that sounds a lot like Trump and the Republicans in 2016 but I think it’s different. The Dems have had 3 years to get to know Bernie and he’s not running away with it. He has not swayed that other faction of the party as Trump eventually did. I believe there will be chaos right up to the convention and no one is going to have enough votes. It will be decided at the convention.