NEW YORK (MarketWatch) — Complacency is dangerous, so it was no surprise to see some market jitters ahead of Sunday’s referendum that saw, as expected, citizens of the Crimea region vote to secede from Ukraine, setting the stage for the return of the Black Sea peninsula to Russia.

Amid tensions between Ukraine and Russia, the vote produced what most observers saw as a foregone conclusion: Reunification with Russia.

Late Sunday exit polls showed 93% of voters in Crimea chose to secede from Ukraine and rejoin Russia. The U.S. immediately said the vote violated Ukraine’s constitution and was held under “threats of violence and intimidation from a Russian military intervention that violates international law.”

Ukraine and the European Union also contend the referendum was illegal. But most observers expect Russia to move quickly to reabsorb the region following the ballot. Many also see little prospect for long-lasting market turmoil barring a significant escalation of tensions or violence, with the U.S. and Western powers in position to do little beyond imposing sanctions on Moscow.

A vote in favor of rejoining Russia would likely be followed by a round of U.S.- and European-led sanctions against Moscow. But that scenario is already “baked in the cake” from a market perspective, said Ed Lalanne, strategist at Macro Risk Advisors, a New York firm that advises institutional investors.

Russian President Vladimir Putin.

U.S. stocks fell ahead of the vote, with the S&P 500 SPX, -1.11% and the Dow DJIA, -0.87% posting their biggest weekly declines since late January. While analysts cited jitters over Ukraine as a factor, investors are also weighing signs of a slowdown in China and gauging the Federal Reserve’s effort to scale back monetary stimulus. Reports Thursday that Russia had massed troops and armored vehicles on Ukraine’s eastern border didn’t help the tone.

Gold and oil futures both gained ground on Friday, though oil posted a weekly decline. Talks between U.S. Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov didn’t produce a breakthrough.

Equity markets in the U.S. and elsewhere are unlikely to react much to Sunday’s expected result, Lalanne said. However, any sign Russia is preparing for military action with designs beyond the Crimea to other predominantly Russian-speaking portions of Ukraine or a round of heavier-than-expected Western sanctions that prompt a harsh response from Moscow would be likely to create turmoil.

Indeed, Russ Koesterich, chief investment strategist at BlackRock, noted that while events in Ukraine temporarily sent markets reeling earlier this month, stocks rebounded within 48 hours to set new highs.

“Does this suggest that events in Ukraine don’t matter to markets? The short answer is no,” Koesterich said, in a note. “However, investors are unlikely to respond to the events in Ukraine without a significant escalation in violence or clear evidence linking the events to the global economy, such as a disruption of oil or gas markets.”

With that in mind, here’s a look at how markets could react to Sunday’s vote:

Energy

Let’s start with oil and natural gas. Both jumped in late February and early March as tensions rose and Russian-backed forces took control of the regional parliament and swarmed Crimea. Memories of how Russia twice shut off natural-gas exports to Ukraine in the last decade were briefly revived. But Nymex WTI crude has since sunk back below $100 a barrel, while gas futures have also retreated.

Nymex April crude futures CLJ24, rose 69 cents, or 0.7%, to settle at $98.89 a barrel, but futures lost around 3.6% this week on a nearby-contract basis, undercut by China worries.

“On the oil side, Crimea is a mild form of risk premium supportive to U.S. crude and slightly supportive to Brent,” said Richard Hastings, macro strategist at Global Hunter Securities.

The U.S. government on Wednesday announced it would make a “test” sale of oil from the Strategic Petroleum Reserve, a move some commentators viewed as a warning to Moscow, though many industry observers dismissed the measure as a purely technical operation. See: Oil sale from SPR raises question of timing, politics.

“If commentators were right in seeing this as a signal to Russia, we would tend to say that this signal will be too weak to reach the Kremlin. It would be a different story if crude exports were to be allowed (temporarily), as this should effectively pressure the Brent/Urals complex by helping Europe to decrease its dependence on crude imports from the East,” wrote analysts at JBC Energy.

If there is a market likely to do something “crazy” in the aftermath of the vote, it’s crude oil, Lalanne said, emphasizing, though, that any strong reaction remains unlikely.

Gold

The yellow metal is a traditional safe haven. April gold rose $6.60, or 0.5%, on Friday to settle at $1,379 an ounce. Gold saw a 3% weekly advance, contributing to its 2014 rebound, but analysts remain reluctant to fully tie recent strength to worries over Crimea.

“The Crimea situation may be an ancillary, emotional facet to the price of gold, but I tend to believe that the price fluctuation [Thursday] is more so related to economic and market results,” said Adam Koos, president and portfolio manager at Libertas Wealth Management Group.

Emerging markets

If problems in Crimea are going to have an immediate impact, emerging markets would seem a logical place to start. But the run-up to the vote is offering little sign that fears have spread beyond Russia and Ukraine, who are dealing with significant economic problems of their own.

The Russian ruble and the Ukraine hryvnia have both plunged since the crisis. Russia’s MICEX stock index XX:MICEXINDEXCF trimmed an earlier decline but still fell 0.7% on Friday, contributing to a 7.4% weekly loss and a drop of more than 14% since the beginning of March.

Beyond the local impact, however, “if we go by asset performance over the past few weeks, the Ukraine crisis has been broadly dismissed by global emerging markets,” wrote analysts led by Benoit Anne at Société Générale, in a note.

“Of course, there has been significant differentiation across markets, but, essentially, the market stress has been confined to Russia and Ukraine,” they said, noting that even the Polish zloty EURPLN, -0.01% USDPLN, -0.01% , which is viewed as a proxy hedge for Central Europe, has slipped only 2% since the start of the crisis.

Crimea referendum: What you need to know

Ukraine as a whole, meanwhile, is confronting a dire situation and is seeking an International Monetary Fund bailout.

Ukraine faces a steep recession, a situation comparable to the plight faced by Cyprus last year, said Markus Schomer, chief economist at PineBridge Investments. And, much like the Cypriot crisis, the contagion risk is likely to be minimal, he said, in a note.

“Ukraine’s problems are unique to its geographic situation, and the most affected economy other than its own is likely to be Russia, which holds Ukrainian debt and whose banks own large stakes in their Ukrainian competitors,” he said.

Fixed income

Bond investors aren’t likely to leave their positions on the table going into the weekend. But a vote to annex Crimea to Russia won’t necessarily drive Treasury prices higher and yields lower, given that such an outcome is already largely expected by the market, said Jonathan Lewis, chief investment officer at Samson Capital Advisors.

The more important factor will be how the involved parties respond and the specifics of when the conflict plays out.

Treasurys surged on Thursday, dragging down the yield on the 10-year Treasury note US:10_YEAR by 9 basis points to 2.647%. Treasurys gave back some gains Friday, with the 10-year yield was edging up by around a basis point on Friday.

“When you are looking at a conflict, there’s no one day where it occurs,” Lewis said. “It seems reasonable that people are position squaring going into the weekend.”

Foreign exchange

It’s not so much the outcome of the vote that will trigger a reaction in currencies but rather how officials in the United Nations, U.S. and European Union respond, said Brad Bechtel, managing director at Faros Trading.

That includes “the extent [to which] they become very vocal about the next steps,” he said.

In that scenario, expect movement in the currencies of neighboring countries, including Poland, Hungary, Turkey and Russia. “Those are the primary emerging-market currencies that are right next to the situation and very vulnerable to the reactions,” he said.

Worst case

Of course, investors must be wary of complacency. And the Crimea is undoubtedly reasserting itself as a global geopolitical flash point, so it pays to remain aware of the risks.

While most analysts doubt Putin would attempt to up the stakes by pressing for control of other Russian-speaking regions of Ukraine beyond Crimea, that possibility can’t be totally dismissed.

“Much is at stake this weekend,” said Bernard Baumohl, chief economist at the Economic Outlook Group in Princeton, N.J., in a note.

Will Putin “double down and unleash war against Ukraine? Such an act raises the specter of a direct military confrontation” between the U.S. and Russia, Baumohl said. “Or will world leaders, and, particularly, Putin’s fellow oligarchs, who worry about losing access to their wealth outside their country, pressure him to seek a diplomatic solution to this crisis?”