Jeff Kleintop, chief market strategist for LPL Financial, wrote in a research note, "If a civil war is avoided in Ukraine, and unrest remains contained and does not spread to other Ukraine territories or into Belarus and Kazakhstan, then much like with Syria last September, the issue won't go away but the impact on markets should fade."
(Read more: Worst day in a month for Dow, S&P, as hit by Ukraine crisis)
Russia has legitimate interests in Crimea (it provides ocean access, and the people are primarily ethnic Russians), Kelly said, there are a number of reasons for Russian President Vladimir Putin not to overplay his hand and involve Russian troops in fighting in Ukraine.
"Ukraine is a great place to own if you're playing a game of Risk; otherwise. you want someone else to own it," he said, adding that Ukrainians will not let Russia overtake their country without a fight.
(Read more: Russian energy a threat to Europe but not the US)
Putin will likely look to avoid acting in a way "that invites large sanctions against it from the West, which could impact the Russian economy," Kelly said.
U.S. companies with operations in Russia or Ukraine might also be affected by embargoes and trade restrictions, said Marc Chandler, currency strategist at Brown Brothers Harriman.
"These potentially include Pepsi, Alcoa, Abbott Labs, Dupont and General Dynamics," Chandler said.
"The most likely scenario is that we end up in a few days or few weeks with some kind of standoff that effectively recognizes Russia's interests in the region, or in Crimea, and also allows the Ukraine to make its way in the world," Kelly said.
(Read more: US, EU ready sanctions as Russia denies ultimatum)
But, he said, Monday's slide in U.S. and global equities is a logical response to the conflict, given its potential to escalate.
"So far," Kelly added, "markets are reacting to heightened risks rather than actual economic damage."
—By CNBC's Kate Gibson