David Jackson

USA TODAY

Donald Trump's nomination of Rex Tillerson to be secretary of State sets up a confirmation battle over the ExxonMobil CEO's business ties to Russia, a fight that could include pushback from some Senate Republicans.

While Democrats and some GOP members raised questions about Tillerson's relationship with Russia — which is accused of interference in the recent presidential election — Trump praised his fellow businessman Tuesday as "a world class player" who has led one of the world's largest corporations.

"His tenacity, broad experience and deep understanding of geopolitics make him an excellent choice for Secretary of State," Trump said in a statement formally announcing the nomination.

In his new role at the State Department, Trump said Tillerson would "promote regional stability and focus on the core national security interests of the United States. Rex knows how to manage a global enterprise, which is crucial to running a successful State Department, and his relationships with leaders all over the world are second to none."

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In a statement, Tillerson said he shares Trump's "vision for restoring the credibility of the United States’ foreign relations and advancing our country’s national security." The nominee pledged to "focus on strengthening our alliances, pursuing shared national interests and enhancing the strength, security and sovereignty of the United States.”

The Senate must still confirm Tillerson, and some members of the Republican majority have raised the Russia issue.

"I expect the US-Russian relationship to be front and center in his confirmation process," said Sen. Lindsey Graham, R-S.C.

Tillerson's ExxonMobil duties involved working on major oil projects with Russia, including a partnership with the Russian oil giant Rosneft.

In 2013, Russian President Vladimir Putin awarded Tillerson the Order of Friendship, one of the highest honors the nation bestows on foreign citizens.

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Florida Sen. Marco Rubio — one of Trump's rivals in the Republican primaries, and a lawmaker who tweeted he did not want a "friend of Vladimir" at the State Department — said he has "serious concerns" about Tillerson's nomination.

"The next secretary of State," Rubio said, "must be someone who views the world with moral clarity, is free of potential conflicts of interest, has a clear sense of America's interests, and will be a forceful advocate for America's foreign policy goals."

Senate Majority Leader Mitch McConnell, R-Ky., praised the nominee and expressed support. McConnell said, "we need a full review of our national security policy, and I know Rex will face each problem head on with American interests and security as his top priority."

Trump and aides floated Tillerson's name throughout the weekend, in part to gauge the reaction of lawmakers.

Tillerson — and other Trump nominees — would pass Senate confirmation if Republicans are united in support.

Thanks to Senate rule changes made by Democrats when they had the majority, critics cannot filibuster nominees, forcing supporters to break the impasse by rounding up 60 votes in the 100-member chamber.

Nominees need only a simple majority, and the next Senate will have 52 Republicans.

Sen. Bob Corker, R-Tenn., chairman of the Senate Foreign Relations Committee and a candidate for secretary of State himself, indicated support for Tillerson, calling him "a very impressive individual" with "an extraordinary working knowledge of the world."

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During an unusually public interview process, Trump's other State Department candidates included 2012 Republican presidential nominee Mitt Romney, ex-New York City mayor and top surrogate Rudy Giuliani, and retired general and ex-CIA director David Petraeus.

New York Sen. Charles Schumer, the incoming Senate Democratic leader, has pledged thorough hearings, telling CBS This Morning that Tillerson "will be questioned thoroughly should he be the nominee and all of these allegations and talks about his closeness with Putin will come forward."

Sen. Chris Murphy, D-Conn., said Tillerson "has spent his entire career putting oil company profits first and the interests of his country second," and added that "it’s fantasy to think he will magically change his stripes once in office. The people I represent in Connecticut deserve better."

Environmentalists are also protesting the selection of an oil company executive to be the nation's top diplomat.

The Conservation Law Foundation said Trump's pick is "his latest and most egregious step in turning the federal government, and stewardship of the global environment, over to a cabal of corporate extremists with proven disdain for science, stewardship, public service, and the common good."

The Trump team cited pointed to endorsements from past Republican foreign policy officials, including ex-secretary of State Condoleezza Rice and former Defense secretary Robert Gates. (In a statement, Gates pointed out that ExxonMobil is a client of the consulting firm run by him and Rice.)

In a statement, Rice said that Tillerson brings "remarkable and broad international experience" to the State Department job.

The Tillerson nomination comes amid news reports that the CIA believes the Russians interfered in the election by hacking Democratic officials' email accounts, seeking to discredit Democratic candidate Hillary Clinton and promote Trump's chances.

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Trump disputed the idea that Russia hacked the Democrats, saying it could just as easily have been China, another country, or an independent actor. His aides said Democrats are pushing the Russia claims as part of an effort to de-legitimize the emerging Trump presidency.

The president-elect and aides said Tillerson's relationship with Russia is strictly business, based on his job with Exxon and Russia's large oil deposits.

A native Texan and graduate of the University of Texas at Austin, Tillerson joined Exxon in 1975 as a production engineer, according to the Trump transition team statement. Rising through the ranks of management, Tillerson became chairman and CEO of the board on Jan. 1, 2006.

In a weekend interview with Fox News Sunday, Trump said Tillerson's "great advantage is he knows many of the players, and he knows them well. He does massive deals in Russia. He does massive deals for the company — not for himself — for the company."