At the state/local level and for federal legislators, it's about a 95% chance your local Republicans are more pro-gun than your Democrats (in 4% of the remainder, both are both equally pro-gun, 1% a very rare scenario when a Fuddy old Republican is actually more anti-gun than an upstart Democrat). There's also those races where the pro-gun candidate is a hopeless long shot, or essentially indistinguishable from the anti-gun candidates.
At the presidential level, the choice is easy; there is no choice. Neither candidate is particularly pro-gun in any way that matters, both are actively proposing additional restrictions of varying severity. Both support or have recently supported the same sorts of restrictions, regardless their current positions. Neither has any kind of coherent understanding of gun rights issues (see sig line for a particular gem from the last debate, in response to a claim Heller was about child-safety). Didn't have to end up this way, but populism is a symptom of a people not thinking clearly, so in retrospect it's no surprise we collectively acted counter-productively. Taking an even longer view of history, we basically haven't had a pro-gun president since before the Great Depression, so it's a bit silly to think our 'salvation' would come at the hands of *any* chief executive; barking up the wrong tree.
To a certain extent, the same can be said of the Supreme Court, which has proven itself incapable of single-handedly protecting our rights, whether or not they are 'friendly' to us (Heller and McDonald have proven to be almost unassailably brilliant opinions with a few glaring but self-defeating flaws, and have been promptly ignored or refuted outright by nearly every single case where their precedent should be applicable). Between the decline of respect for SCOTUS by lower courts, and the decline of respect for SCOTUS by everyone else paying attention due to numerous very poorly reasoned opinions over the last decade (at an accelerating pace), they are rapidly losing the moral/legal authority to settle contentious issues like these one way or the other (a disturbing trend reminiscent of the Dred Scott v Sandford slavery decision, which heralded the American Civil War). Once again, it didn't have to be this way, but as with the presidential primaries, numerous blunders and missed opportunities delivered us to our current situation.
Luckily, the state/local races are the most immediately important ones and the most easily won/influenced by any given gun owner, in light of how poorly federal gun control efforts have fared of late (that said, if the Senate flips decisively we'll be in for a ride, but that's a constant threat). For the average gun owner, the primary threat to what you have *now* is from your own state legislators passing AWBs. Assuming things tend toward the middle as opposed to the worst or best possible outcome, we'll have divided government for the foreseeable future, and it won't matter all that much who is in the Big Chair. There will still be pro-gun voices able to filibuster opponents (ironically, ones that will receive a lot of undue blame in a few weeks)
Now, the difference in who gets elected to prez and legislature (and eventually appointed to SCOTUS) matters greatly, but only in the long run, and our side has clearly ceded our field position as far as our long term strategy; it's out of our hands for the time being because of our poor choices. Even if this election was a landslide for gun rights (it easily could have been had primary voters been thinking rationally & had the Republican party sought to defend itself from viral insurgents as well as the Democratic party does) it would be nearly a decade before we'd see any rewards, so the reverse is likely true now that this is no longer a reasonable possibility. If bad SCOTUS picks get on the bench, it will still be years, and multiple election cycles before they bear their poison fruit. Plenty of time for our side to take defensive measures ***IF*** we can manage to learn the correct lesson for once, and nominate leaders with a coherent understanding of the issues, and realistic goals to be attained. Only this way can we pivot from a defensive, reactionary stance that favors obstruction & protest (congress' resistance of gun control bills & Trump) to an offensive stance where gun laws are over/re-written or repealed outright. This has always been the Democrats' strength, and the Republicans' weakness, however (largely stemming from the reality that Republicans can't as easily bribe the majority of their diverse groups of supporters into common-cause they way Democrats can with spending bills)
We have no reason to fear a rapid slide into despotism, at least not on this particular issue, yet. There is simply too much money involved among too many voters for confiscatory policies at this time, too many oxen to be gored. Disobedience would be rampant, and crackdowns would likely result in a significant level of civil unrest or assassinations (which would self-reinforce the crackdown and rapidly pull us into despotism, accompanied by ever-increasing resistance factions). Our side has made huge sustained gains since the AWB expired, and it will take easily a decade for the anti's to gradually undo this through incremental measures (assuming their base of billionaire support doesn't die with Hillary and the rest of her generation, which are all pushing seventy years or more at this point)
Long/short; vote for who you want for president, or nobody. It really won't amount to a hill of beans in any foreseeable timespan, since much larger forces dictate our fate, and the presidency is a poor tool for *us* in any case. But for your local and state elections, and congressional representatives, your vote is far more significant in its ability to direct the course of events in the near future (and to a lesser extent, longer term). If you are in a swing state and it will bother you for it to go blue, vote red, but don't hold any illusions it's of any ultimate significance for gun rights compared to the down-ballot races, and for those races, realize it's pretty much guaranteed the red party will do better for us than the blue one.
TCB