According to Gallup, of all the people who spoke at the Democratic and Republican conventions, only Sen. Ted Cruz of Texas saw much change in his approval numbers. Prior to appearing at the convention in Cleveland, Cruz had a net positive rating from Republican voters, but he’s underwater now.
I don’t think that matters at all for Cruz, though, unless Trump somehow wins the presidency. And, in that case, I doubt Cruz has a political future anyway.
All you have to do is think to the day after the election in November. Assuming Trump loses, as he is now universally expected to do, he’ll be in the same (basic) category as Dole, McCain and Romney. Those losers retained some basic level of reverence and respect both within the party and with the media, but they were also blamed for running the wrong kind of campaign with the wrong kind of values. As conservatism can never fail, they were each accused of selling conservatives out, and people who had run to their right in the primaries and lost were seen as more credible than they were with the party’s non-establishment faithful.
The recriminations against Trump are likely to dwarf what we saw with Dole, McCain and Romney, though, so Cruz stands to benefit more than previous failed challengers. In the end, it will be better to have failed to endorse Trump than to have endorsed him, and Cruz is the most prominent of non-endorsers.
On the other hand, the conservative alternatives to previous nominees haven’t fared all that well. Pat Buchanan went nowhere as a Reform Party candidate in 2000, although Florida Jews accidentally voting for him on the butterfly ballot in Palm Beach may have inadvertently ripped a hole in fabric of the universe and caused a catastrophe from which we (and the Middle East) cannot seem to escape.
I don’t know how convincingly you can argue that Romney ran to McCain’s left in 2008, and the more obvious conservatives like Huckabee didn’t rebound well in 2012. Rick Santorum seemed genuinely surprised that his second place finish in 2012 didn’t make him next in line for the nomination in 2016.
Cruz will have more credibility for having battled with Trump, but that doesn’t assure him of a bright future or a clean shot at the 2020 nomination.