Underdog candidates are "insurgents." Campaigns fight for votes in "battleground states." And as this 2016 race reaches its decisive days, the prospect of "revolution" hangs in the air.

It has been a relentless theme of the past 18 months. Bernie Sanders called for a "political revolution" in almost every speech, as he sold a policy outline meant to upend the economic status quo. Donald Trump has been using such terms for years, though in darker tones.

And in more graphic detail than the American public has ever seen. The Republican nominee and his allies -- many of them drawing on the tea party's glorification of Revolutionary War-era imagery -- have colored this election season with the rhetoric of war and bloodshed. As if making America "great again" were as much a military campaign as a political one.

As Mitt Romney fell to President Barack Obama on election night in 2012, Trump -- armed with his phone and incomplete information -- tweeted that Obama had lost the popular vote, then called for "a revolution in this country!" He deleted that post but not the one calling for a "march on Washington."

On Wednesday, former Rep. Joe Walsh became the latest in a long line of high-profile Trump supporters to invoke a bloody revolt and firearms in response to the GOP candidate's potential defeat on Election Day.

"On November 8th, I'm voting for Trump. On November 9th, if Trump loses, I'm grabbing my musket," Walsh wrote to his more than 78,000 followers. "You in?"

On November 8th, I'm voting for Trump.



On November 9th, if Trump loses, I'm grabbing my musket.



You in? — Joe Walsh (@WalshFreedom) October 26, 2016

What did that mean, exactly? CNN's Jake Tapper asked.

"It means protesting," Walsh replied . "Participating in acts of civil disobedience. Doing what it takes to get our country back."

Walsh has gone down this road before. After five Dallas police officers were killed by a sniper in July, he tweeted, "This is now war. Watch out Obama. Watch out black lives matter punks. Real America is coming after you."

Twitter locked his account and forced him to delete the message, Walsh told CNN's Don Lemon , adding that he "didn't intend to say everybody go threaten Barack Obama or incite violence against Barack Obama."

Trump has played at this with jarring regularity, creating a series of tense flashpoints during the course of the campaign. On October 13, he told supporters that, in the eyes of the global power structure they sought to topple, the coming election "is a war."

"And for them," he continued about the opposition, "nothing at all is out of bounds. This is a struggle for the survival of our nation, believe me. And this will be our last chance to save it on November 8 -- remember that."

Language that in past years might have set the political world on its heels has often passed by without much notice in 2015 and 2016. Only in a campaign of near daily absurdities and broken taboos could a sitting governor, Kentucky Republican Matt Bevin, muse at length but without much notice over "whose blood" will be shed in the aftermath of his candidate's loss.

"I want us to be able to fight ideologically, mentally, spiritually, economically, so that we don't have to do it physically, but that may, in fact, be the case," he said at the Values Voter Summit in September.

"The roots of the tree of liberty are watered by what?" Bevin asked in remarks first surfaced by Right Wing Watch . "The blood of who? The tyrants, to be sure. But who else? The patriots. Whose blood will be shed? It may be that of those in this room. It might be that of our children and grandchildren."

Violent rhetoric, matched with allusions to weapons and combat, have become almost inescapable.

Both on social media and in a recent speech , Milwaukee County Sheriff David Clarke, who addressed the Republican National Convention in Cleveland this past July, has claimed the election is "rigged" and declared it "pitchfork and torches time in America!"

He is not the first Trump ally to connect the "rigged" vote meme -- one that persists, again, despite a complete lack of evidence -- to armed conflict in the aftermath.

Right-wing gadfly and longtime Trump confidant Roger Stone pushed the narrative during an interview with Breitbart's Milo Yiannopoulos during an August conversation

"I think (Trump's) gotta put them on notice that their inauguration will be a rhetorical -- and I mean civil disobedience, not violence -- but it will be a bloodbath," Stone said.

Writing in the right-wing site WorldNetDaily, Pat Buchanan -- a former Nixon and Reagan White House staffer and presidential candidate -- compared the US in 2016 to Soviet-controlled Prague and Egypt under the heavy hand of Hosni Mubarak, then asked, "When do we have our American Spring?"

A Clinton victory, which Buchanan conceded the polls were predicting, promised "a bad moon rising."

"And the new protesters in the streets," he added, jabbing at 1960s-era student radicals, "will not be over-privileged children from Ivy League campuses."

In 2016, the furor has largely resided with slightly older voters, usually white and often anxiety-stricken over their lost status and diminishing economic opportunity.

And so there was Rhonda, speaking into a microphone held by a fellow Trump supporter at an event on October 11 in Iowa, with a message for Republican vice presidential nominee Mike Pence.

"Our lives depend on this election. Our kids' futures depend on this election, and I will tell you just for me, and I don't want this to happen, but I will tell you for me, personally, if Hillary Clinton gets in, I myself, I'm ready for a revolution," she said , her voice breaking up, "because we can't have her in."

Pence pulled back, waved his hand and shook his head.

"Don't say that," he replied -- then added in a more relaxed voice: "There's a revolution coming on November 8. I promise you."