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Congressional Republicans have long railed against President Obama's approach to nuclear negotiations with Iran. Now that the GOP has control of both the House and Senate, they're preparing to confront him on the matter this month.

As the 114th Congress sorts out its priorities, voting on the Keystone XL pipeline and sanctions on Iran have risen to the top of the agenda. GOP Sen. Mark Kirk of Illinois told Fox News last week that Majority Leader Mitch McConnell has said the Senate's first vote will be on the Keystone pipeline. "He has also said the second big vote will be on Iran sanctions," Kirk added, "so I would expect that coming up."

Republicans in Congress who think the administration is not forceful enough in its negotiations with Iran have clamored for more say in the process, and some among them wish to impose harsh sanctions on the country that would go into effect if negotiators fail to reach a deal. "This is one of the biggest issues we'll be dealing with," Sen. Bob Corker of Tennessee told Fox News on Sunday. "And for Congress not to have a role is totally inappropriate."

When the Senate was controlled by Democrats, Obama relied on then-Majority Leader Harry Reid to stop the House's attempts to insert Congress into the process, but this week's power shift means Republicans have a much better chance of passing Iran-sanctions legislation.

There are two main bills that are likely to be the focus of the Republican push on Iran. The first, known as the Kirk-Menendez bill, would increase sanctions on Iran if it abandoned negotiations. Introduced in December 2013, it floundered in the Senate the following month.

Republicans will most likely resurrect the bill for a vote this month. Speaking at a joint press conference with Israeli Prime Minister Benjamin Netanyahu last month, Sen. Lindsey Graham of South Carolina said that in January, "there will be a vote on the Kirk-Menendez bill, bipartisan sanction legislation that says, if Iran walks away from the table, sanctions will be reimposed; if Iran cheats regarding any deal that we enter to the Iranians, sanctions will be reimposed."

A second piece of legislation that could come up this month was initially put forward by Graham, along with Sens. John McCain and Kelly Ayotte, in November. The bill, which the Democratic-controlled Senate did not vote on, would allow the foreign relations committees in both chambers to review any nuclear deal with Iran before passing it to Congress for a vote.

Top Republicans seem confident they'll be able to pass the legislation this month. "I think we'll have a supermajority, a veto-proof majority, to impose additional sanctions on Iran and to require the administration to come before Congress for approval of any deal that [Obama] has with Iran," Sen. Marco Rubio of Florida told NPR last week.

To reach that majority, the GOP needs Democratic senators to vote with them. Kirk says some are already on board. "I have 17 Democrats with me."¦ We have a shot at even getting to a veto-proof majority in the Senate. That's what we'll be working on, a good bipartisan vote," he told Fox News.

But if Republicans can't find the 67-vote majority, any legislation Congress does pass in January faces the president's veto. Obama will veto a bill approving the Keystone XL pipeline if it passes Congress, the White House said, and a similar veto of Iran-sanctions legislation would set up a contentious beginning to the last two years of his presidency.

This article is from the archive of our partner National Journal.

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