Conservative punditry tends of focus on the challenge facing Republicans in retaking the White House. But let's briefly consider the challenges facing Hillary. Seems to me there are at least two significant drag factors on her bid:
i) Although I don't know this for a fact, I suspect that Democrat losses in Congressional and gubernatorial elections during Obama's tenure owe a lot to Obamacare. It's a ball-n-chain for the Democrat party. Tens of millions of Americans have lost their coverage, had to change doctors, had to get reinsured at higher rates, with higher premiums, deductibles, and copays, or face increasing fines. And this hits swing voters.
Even if Hillary privately had misgivings about Obamacare, she won't distance herself too much from Obama's signature legislation because she seeks his support, or at least wishes to avoid his opposition, during her campaign.
ii) The Liberal establishment has decreed that it's taboo to even suggest that Islam is a source of terrorism. You have a handful of prominent atheists who do so, but they are constantly on the defensive for saying so.
Many Americans feel the gov't is willfully out of touch with the public on this issue. Not only does the gov't refuse to protect us from domestic jihadism, but it protects domestic jihadists. Whenever there's an attack, the reflexive impulse of Democrats is to disarm the general public, making us even more vulnerable. Instead of defending us, they wish to make us defenseless. They won't defend us or let us defend ourselves.
And Hillary can't bring herself to break that taboo. Weakness on this issue will hurt her.
I don't know how damaging these two issues will be to her presidential aspirations. But these are obstacles to her political ambitions.
Thus far, she's never had to appeal to anyone outside the Democrat constituency. She ran and won in the blue state of New York. And she's run in Democrat primaries. She's untested when it comes to the general electorate.