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The House on Wednesday is expected to vote onand likely pass – an amendment authorizing President Obama to arm and train moderate Syrian rebels in his war with the Islamic State, but don't expect the vote to fall neatly along party lines.

While the measure has drawn support from both the Republican and Democratic leadership, rank-and-file members across the political spectrum have raised concerns about it in recent days. The opposition is likely not enough to derail the proposal, but it could deny Obama the overwhelming vote of support he wants from Congress.

"I think what we’re going to see is bipartisan opposition to the amendment, and bipartisan support," senior GOP Rep. Tom Cole (Okla.) said in a floor speech Tuesday as the House opened six hours of debate on the provision.

The amendment on arming the Syrian rebels is being attached to a larger spending bill that Congress must pass before it leaves Washington this week to avoid a government shutdown at the end of September. Because Obama has not asked for a formal vote authorizing the use of military force to take out ISIS – he says he doesn't need it – this is the closest Congress will come to taking a position on the plan he laid out in a primetime speech last week.

The Senate is expected to vote later this week, assuming the House measure passes.

In speeches on Tuesday, concerns about Obama's plan ran the gamut, from Republicans who didn't think it went far enough, liberals who worried about starting another war in the Middle East and others who feared that training and arming unknown elements in Syria would come back to haunt the United States.

"The president's proposal will not work. I will not support it," conservative Rep. Dana Rohrbacher (R-Calif.) said.

On the other side of the political spectrum, liberal Rep. Barbara Lee (D-Calif.) raised some of the same points she made 13 years ago when she was the only member of the House to oppose then-President George W. Bush's request for an authorization of force against terrorists after the attacks of Sept. 11, 2001.

Lee said the question in Congress "was more complex than just an up-or-down vote on arming and training members of the Free Syrian Army."

The consequences of this vote, whether it's written in the amendment or not, will be a further expansion of a war currently taking place and our further involvement in a sectarian war."

Conservative Rep. Louie Gohmert (R-Tex.) warned that Obama risked making the same mistake that he argued he made when he went into Libya in 2011 – arming rebels that would then use those weapons against the U.S., as he said happened in Benghazi on Sept. 11, 2012.

One of the big problems, too, is when we go in and train, as this president wants to do for Syrians, they learn our tradecraft [and] they use it against us as they did in Benghazi.

We’re in big trouble here. Our action will unify radicals against us."

Still, other members in both parties argued in favor of the president's request, either because they approved of the limited mission he outlined or because they simply felt the U.S. had no other choice but to go after ISIS.

Rep. Jim Moran (D-Va.) said the situation in Iraq and Syria will not "stay static. It is is either going to get worse or it is going to get better."

"ISIS, if it is not confronted, will grow," he said.

Republican Rep. Dennis Ross (Fla.) said that he'd vote for the plan even though he felt it wasn't sufficient to destroy the Islamic State.

While this amendment does not represent my ideal military strategy against ISIL, I believe Congress is fulfilling its constitutional duty today, and I stand in support of its efforts."

If the measure passes, it will be because of intense lobbying from the Obama administration and leaders in both parties in Congress. Speaker John Boehner (R-Ohio), usually a foe of the president, has tried to rally Republicans in support, while Minority Leader Nancy Pelosi (D-Calif.), a vocal opponent of the Iraq war, pitched reluctant Democrats on it Tuesday afternoon.

But lawmakers were also facing pressure from outside the Capitol, including from former colleagues like Allen West (R-Fla.), who weighed in on Twitter:

This article is from the archive of our partner The Wire.

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