So do Democrats and pretty much everyone else. It's naive to think that this can easily be reduced to one party, for if that were true, we wouldn't be discussing the USA right now. A badly informed populace does not make informed decisions.
To be entirely fair, Democratic fear-mongering is at least least loosely based in reality. They talk about things like welfare, the job market, discrimination- bread and butter stuff, basically, and which generally reflect the logical (if not necessarily the
likely) outcome of Republican policies. Republican fear-mongering, in contrast, tends to revolve around narratives of cultural decline and impending federal tyranny (often verging on conspiracy, to the understandable embarrassment of moderate Republicans), and appeals not to the honest concerns of the precarious poor, but to the cultural neuroses of a white middle class in decline.
Now, I don't think that this is a matter of virtue on the part of the Democrats or of wickedness on the part of the Republicans, so much as it reflects their respective social bases. (In both camps, cynicism is the rule.) The Democrats primarily appeal to the traditionally-subordinate parts of society- the poor, the young, minorities, etc.- whose concerns lean heavily towards the everyday, while the Republicans primarily appeal to the traditionally-dominant parts of society, who while hardly lacking their own everyday concerns, have more time to fret about their declining social hegemony. But it's a real distinction, and one worth remembering.